Topics

[Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

Patrick McAneny
 

Craig , Your original post seemed to support locating breakers far from the power source , however this post seems to acknowledge the protection offered by locating breakers as close as possible to the battery bank. You even pointed to boat that burned up cables as a result of a short . Now I must be missing something . When I build a house , I have 220v/ 200 amps coming through a  wall , I locate the distribution panel as close as possible to where it comes thru the wall. The electric immediately goes thru appropriate size breakers and passes thru appropriate sized wiring on to  outlets ,  pumps ,etc . In the event of a short there is little chance of the wire being overloaded . You do not use 14g wire with a 20 amp breaker ! In a house you would not run a 220v line to a laundry room and place the breaker on the wall behind the dryer. I have never understood the difference between protecting a boat vs. a house . But , maybe I am missing something, it would not be the first time.
Pat
SM #123


-----Original Message-----
From: sangaris@... [amelyachtowners]
To: amelyachtowners
Sent: Mon, Oct 16, 2017 9:34 am
Subject: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 
Alan,
That seems an excellent idea. I remember that in 2001 I totally redid SM Miss Lindy's wiring (don't recall the hull number) after it completely burned out for the third time. All the heavy cables in the engine room, from battery to starter to generator to main house feeds had melted solid. As I finished up I still had low volts from the engine to the battery.  Traced it to the starting cables having chaffed about 12 inches down inside the PVC pipe from the battery to the engine (that was supposedly there to prevent chafe). Your solution would have prevented much heartache and expense. 
Will be interested in Bill K's bounce. Perhaps the modern distributed systems do incorporate that.
Craig SN#68


---In amelyachtowners@..., wrote :

well said Bill,
BUT that's exactly what we have on our SMs....th e anchor windlass, the genoa furler etc have the breakers at the "other end" of the cables that run from the house bank...and...on the standard setup, there are NO FUSES near the battery connections. 
I've put large Blue Sea fuses in the battery compartment on each of my 3 banks of 4 6V series batteries to try to address these issues.
What have you done ?
Cheers
Alan
Elyse SM437

Craig,

I think you (and Amel in the "old days") are simply missing the point of circuit breakers.  They are most certainly NOT there to protect the anchor washdown pump, or the thruster motor, or any other piece of equipment.  There is nothing a circuit breaker can do to "protect" the pump motor, or other device:  If it shorts, it has already died! If, in normal operation, it draws too much current for the wiring to support, then the wiring is undersized.

Circuit breakers are there to protect the WIRING and prevent the catastrophic results that can occur if a short occurs ANYWHERE that overloads the wiring.  This can occur from many faults, none of them likely, but all with disastrous consequences.  Wire chafe is probably the most common cause on boats, but others happen. I'd guess loose connections are a close second.  

Having a breaker at the far end of the wire, away from the battery, completely misses the point of why it is there in the first place. In my opinion, if you have a circuit breaker at the point of use of the power, you might as well just replace it with a switch--it is essentially useless. 

When I ran a service department for a large charter company, one of the annual safety meetings I ran for for my staff was to dead short circuit a 12 volt battery through 14 gauge wire.  Watching solid copper wire burst into flame and literally explode was a sobering experience for people who could easily get into the habit of thinking "its only 12 volts." It really made the point about why fuses and circuit breakers were essential.

There is nothing at all wrong with distributed CONTROL of an electrical system. That is just fancy electronics.  But... you can not "distribute" protection of the wiring. I have never heard a  good reason to run long lengths of un-fused wiring on a boat--or anywhere else.  It is just dangerous--and for absolutely no benefit.  Dangerous overloads rarely occur because of equipment problems.  They occur because of wiring faults.  Do they happen often?  No, not at all. But when they do, it is truly terrifying.  

C-zone, Ocotplex, etc, are NOT wiring protection systems.  They are not "circuit breakers".  They are CONTROL systems.  Very different animals.

I have seen several boat fires at much closer quarters than I ever hope to repeat, and most of them were electrical in origin, all from things that shouldn't have happened--but did.  

Bill Kinney
Sm160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@..., wrote :

I'd always thought Amel was ahead of the curve with its Distributed Electrical System. That seems to be the direction the industry is going, now with solid state circuit breakers controlled through the NMEA2000 data network. Eliminates the large industrial style circuit breaker panels of yore and adds great flexibility. Check out CAPI2, C-Zone, Octoplex, etc. Seems Amel is going backwards technologically if they're centralizing. Let's see, your anchor washdown pump shorts and rather than it tripping an adjacent breaker it's got to overload a 15 meter long cable run back to the central circuit breaker panel. To say nothing of the excess wiring to give all equipment a "home run". Must be missing something in this discussion.
Cheers, Craig SN68 Sangaris
< br>

Craig & Katherine Briggs SN 68 Sangaris Tropic Isle Harbor, FL
 

Hi Pat, 
Yes, that's why I thought Alan's adding the Blue Sea fuses at the batteries sounded wise. Btw, in my house the distribution panel is smack in the middle of the house which reduces the total amount of wiring. It does, of course, have a main service breaker at the external drop wire, analogous to Alan's Blue Sea fuse. Then there are separate fused disconnects adjacent to heavy loads like the A/C and hot water heater in addition to breakers for those at the distribution panel.

I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs. Alan seems to have a good solution.  And, while the new Amel centralized panel would meet Bill K's criterion, it is (likely) not fused close to the batteries, leaving the same risk of chafe and shorting in either the wires going to the panel or the wires going to the engine & generator starting motors.

I do suspect that the industry will continue to modernize with Distributed electric systems and have not overlooked the risk of shorting in the long runs, although I haven't looked into it enough to know exactly how it is addressed.

Craig SN68


---In amelyachtowners@..., <sailw32@...> wrote :

Craig , Your original post seemed to support locating breakers far from the power source , however this post seems to acknowledge the protection offered by locating breakers as close as possible to the battery bank. You even pointed to boat that burned up cables as a result of a short . Now I must be missing something . When I build a house , I have 220v/ 200 amps coming through a  wall , I locate the distribution panel as close as possible to where it comes thru the wall. The electric immediately goes thru appropriate size breakers and passes thru appropriate sized wiring on to  outlets ,  pumps ,etc . In the event of a short there is little chance of the wire being overloaded . You do not use 14g wire with a 20 amp breaker ! In a house you would not run a 220v line to a laundry room and place the breaker on the wall behind the dryer. I have never understood the difference between protecting a boat vs. a house . But , maybe I am missing something, it would not be the first time.
Pat
SM #123


-----Original Message-----
From: sangaris@... [amelyachtowners] <amelyachtowners@...>
To: amelyachtowners <amelyachtowners@...>
Sent: Mon, Oct 16, 2017 9:34 am
Subject: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 
Alan,
That seems an excellent idea. I remember that in 2001 I totally redid SM Miss Lindy's wiring (don't recall the hull number) after it completely burned out for the third time. All the heavy cables in the engine room, from battery to starter to generator to main house feeds had melted solid. As I finished up I still had low volts from the engine to the battery.  Traced it to the starting cables having chaffed about 12 inches down inside the PVC pipe from the battery to the engine (that was supposedly there to prevent chafe). Your solution would have prevented much heartache and expense. 
Will be interested in Bill K's bounce. Perhaps the modern distributed systems do incorporate that.
Craig SN#68


---In amelyachtowners@..., <divanz620@...> wrote :

well said Bill,
BUT that's exactly what we have on our SMs....th e anchor windlass, the genoa furler etc have the breakers at the "other end" of the cables that run from the house bank...and...on the standard setup, there are NO FUSES near the battery connections. 
I've put large Blue Sea fuses in the battery compartment on each of my 3 banks of 4 6V series batteries to try to address these issues.
What have you done ?
Cheers
Alan
Elyse SM437

Craig,

I think you (and Amel in the "old days") are simply missing the point of circuit breakers.  They are most certainly NOT there to protect the anchor washdown pump, or the thruster motor, or any other piece of equipment.  There is nothing a circuit breaker can do to "protect" the pump motor, or other device:  If it shorts, it has already died! If, in normal operation, it draws too much current for the wiring to support, then the wiring is undersized.

Circuit breakers are there to protect the WIRING and prevent the catastrophic results that can occur if a short occurs ANYWHERE that overloads the wiring.  This can occur from many faults, none of them likely, but all with disastrous consequences.  Wire chafe is probably the most common cause on boats, but others happen. I'd guess loose connections are a close second.  

Having a breaker at the far end of the wire, away from the battery, completely misses the point of why it is there in the first place. In my opinion, if you have a circuit breaker at the point of use of the power, you might as well just replace it with a switch--it is essentially useless. 

When I ran a service department for a large charter company, one of the annual safety meetings I ran for for my staff was to dead short circuit a 12 volt battery through 14 gauge wire.  Watching solid copper wire burst into flame and literally explode was a sobering experience for people who could easily get into the habit of thinking "its only 12 volts." It really made the point about why fuses and circuit breakers were essential.

There is nothing at all wrong with distributed CONTROL of an electrical system. That is just fancy electronics.  But... you can not "distribute" protection of the wiring. I have never heard a  good reason to run long lengths of un-fused wiring on a boat--or anywhere else.  It is just dangerous--and for absolutely no benefit.  Dangerous overloads rarely occur because of equipment problems.  They occur because of wiring faults.  Do they happen often?  No, not at all. But when they do, it is truly terrifying.  

C-zone, Ocotplex, etc, are NOT wiring protection systems.  They are not "circuit breakers".  They are CONTROL systems.  Very different animals.

I have seen several boat fires at much closer quarters than I ever hope to repeat, and most of them were electrical in origin, all from things that shouldn't have happened--but did.  

Bill Kinney
Sm160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@..., <sangaris@...> wrote :

I'd always thought Amel was ahead of the curve with its Distributed Electrical System. That seems to be the direction the industry is going, now with solid state circuit breakers controlled through the NMEA2000 data network. Eliminates the large industrial style circuit breaker panels of yore and adds great flexibility. Check out CAPI2, C-Zone, Octoplex, etc. Seems Amel is going backwards technologically if they're centralizing. Let's see, your anchor washdown pump shorts and rather than it tripping an adjacent breaker it's got to overload a 15 meter long cable run back to the central circuit breaker panel. To say nothing of the excess wiring to give all equipment a "home run". Must be missing something in this discussion.
Cheers, Craig SN68 Sangaris
< br>

Craig & Katherine Briggs SN 68 Sangaris Tropic Isle Harbor, FL
 

PS.  Have done some more googling on the subject and it appears the Distributed systems have each of the feeder circuits fused at a bus near the batteries, in addition to the data-controlled breakers near the loads. Just as Alan has done with Amel's "old-fashioned" Distributed system. 
fwiw, Craig


---In amelyachtowners@..., <sangaris@...> wrote :

Hi Pat, 
Yes, that's why I thought Alan's adding the Blue Sea fuses at the batteries sounded wise. Btw, in my house the distribution panel is smack in the middle of the house which reduces the total amount of wiring. It does, of course, have a main service breaker at the external drop wire, analogous to Alan's Blue Sea fuse. Then there are separate fused disconnects adjacent to heavy loads like the A/C and hot water heater in addition to breakers for those at the distribution panel.

I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs. Alan seems to have a good solution.  And, while the new Amel centralized panel would meet Bill K's criterion, it is (likely) not fused close to the batteries, leaving the same risk of chafe and shorting in either the wires going to the panel or the wires going to the engine & generator starting motors.

I do suspect that the industry will continue to modernize with Distributed electric systems and have not overlooked the risk of shorting in the long runs, although I haven't looked into it enough to know exactly how it is addressed.

Craig SN68


---In amelyachtowners@..., <sailw32@...> wrote :

Craig , Your original post seemed to support locating breakers far from the power source , however this post seems to acknowledge the protection offered by locating breakers as close as possible to the battery bank. You even pointed to boat that burned up cables as a result of a short . Now I must be missing something . When I build a house , I have 220v/ 200 amps coming through a  wall , I locate the distribution panel as close as possible to where it comes thru the wall. The electric immediately goes thru appropriate size breakers and passes thru appropriate sized wiring on to  outlets ,  pumps ,etc . In the event of a short there is little chance of the wire being overloaded . You do not use 14g wire with a 20 amp breaker ! In a house you would not run a 220v line to a laundry room and place the breaker on the wall behind the dryer. I have never understood the difference between protecting a boat vs. a house . But , maybe I am missing something, it would not be the first time.
Pat
SM #123


-----Original Message-----
From: sangaris@... [amelyachtowners] <amelyachtowners@...>
To: amelyachtowners <amelyachtowners@...>
Sent: Mon, Oct 16, 2017 9:34 am
Subject: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 
Alan,
That seems an excellent idea. I remember that in 2001 I totally redid SM Miss Lindy's wiring (don't recall the hull number) after it completely burned out for the third time. All the heavy cables in the engine room, from battery to starter to generator to main house feeds had melted solid. As I finished up I still had low volts from the engine to the battery.  Traced it to the starting cables having chaffed about 12 inches down inside the PVC pipe from the battery to the engine (that was supposedly there to prevent chafe). Your solution would have prevented much heartache and expense. 
Will be interested in Bill K's bounce. Perhaps the modern distributed systems do incorporate that.
Craig SN#68


---In amelyachtowners@..., <divanz620@...> wrote :

well said Bill,
BUT that's exactly what we have on our SMs....th e anchor windlass, the genoa furler etc have the breakers at the "other end" of the cables that run from the house bank...and...on the standard setup, there are NO FUSES near the battery connections. 
I've put large Blue Sea fuses in the battery compartment on each of my 3 banks of 4 6V series batteries to try to address these issues.
What have you done ?
Cheers
Alan
Elyse SM437

Craig,

I think you (and Amel in the "old days") are simply missing the point of circuit breakers.  They are most certainly NOT there to protect the anchor washdown pump, or the thruster motor, or any other piece of equipment.  There is nothing a circuit breaker can do to "protect" the pump motor, or other device:  If it shorts, it has already died! If, in normal operation, it draws too much current for the wiring to support, then the wiring is undersized.

Circuit breakers are there to protect the WIRING and prevent the catastrophic results that can occur if a short occurs ANYWHERE that overloads the wiring.  This can occur from many faults, none of them likely, but all with disastrous consequences.  Wire chafe is probably the most common cause on boats, but others happen. I'd guess loose connections are a close second.  

Having a breaker at the far end of the wire, away from the battery, completely misses the point of why it is there in the first place. In my opinion, if you have a circuit breaker at the point of use of the power, you might as well just replace it with a switch--it is essentially useless. 

When I ran a service department for a large charter company, one of the annual safety meetings I ran for for my staff was to dead short circuit a 12 volt battery through 14 gauge wire.  Watching solid copper wire burst into flame and literally explode was a sobering experience for people who could easily get into the habit of thinking "its only 12 volts." It really made the point about why fuses and circuit breakers were essential.

There is nothing at all wrong with distributed CONTROL of an electrical system. That is just fancy electronics.  But... you can not "distribute" protection of the wiring. I have never heard a  good reason to run long lengths of un-fused wiring on a boat--or anywhere else.  It is just dangerous--and for absolutely no benefit.  Dangerous overloads rarely occur because of equipment problems.  They occur because of wiring faults.  Do they happen often?  No, not at all. But when they do, it is truly terrifying.  

C-zone, Ocotplex, etc, are NOT wiring protection systems.  They are not "circuit breakers".  They are CONTROL systems.  Very different animals.

I have seen several boat fires at much closer quarters than I ever hope to repeat, and most of them were electrical in origin, all from things that shouldn't have happened--but did.  

Bill Kinney
Sm160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@..., <sangaris@...> wrote :

I'd always thought Amel was ahead of the curve with its Distributed Electrical System. That seems to be the direction the industry is going, now with solid state circuit breakers controlled through the NMEA2000 data network. Eliminates the large industrial style circuit breaker panels of yore and adds great flexibility. Check out CAPI2, C-Zone, Octoplex, etc. Seems Amel is going backwards technologically if they're centralizing. Let's see, your anchor washdown pump shorts and rather than it tripping an adjacent breaker it's got to overload a 15 meter long cable run back to the central circuit breaker panel. To say nothing of the excess wiring to give all equipment a "home run". Must be missing something in this discussion.
Cheers, Craig SN68 Sangaris
< br>

Bill & Judy Rouse <yahoogroups@...>
 

Bill K and Pat,

I would never say that "I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs."

I would not say anything like that for numerous reasons. I think you know why.

Since Henri Amel is not here to defend his decisions made many years ago, I will remind everyone that at the time these decisions were made they very likely conformed 100% with the regulations in force in Europe and conformed with the thinking at the time. Let's compare Henri Amel's engineering decisions to General Motors at the same time:
- Disintegrating plastic bumper parts
- 4-6-8 engines with 100% failure
- Gasoline to Diesel conversions with almost 100% failure
- Reduction of plasticides in paint which caused paint to fade in 6 years
- Plastic transmission parts which caused a new industry to emerge to repair transmissions
- Fiero & Corvair (one name says it all)
- Foam headliners which fell in 5 years
- Chrome coated plastic which lasted about 2 years
on, and on, and on.

Can one improve on yesterday's technology? Certainly! 
Can one not understand decisions made yesterday? Absolutely!
Should one of us criticize Henri Amel? Never!

Anyway, this is my sermon for the month. I hope that you enjoyed it. 

Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970





On Tue, Oct 17, 2017 at 8:39 AM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Hi Pat, 

Yes, that's why I thought Alan's adding the Blue Sea fuses at the batteries sounded wise. Btw, in my house the distribution panel is smack in the middle of the house which reduces the total amount of wiring. It does, of course, have a main service breaker at the external drop wire, analogous to Alan's Blue Sea fuse. Then there are separate fused disconnects adjacent to heavy loads like the A/C and hot water heater in addition to breakers for those at the distribution panel.

I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs. Alan seems to have a good solution.  And, while the new Amel centralized panel would meet Bill K's criterion, it is (likely) not fused close to the batteries, leaving the same risk of chafe and shorting in either the wires going to the panel or the wires going to the engine & generator starting motors.

I do suspect that the industry will continue to modernize with Distributed electric systems and have not overlooked the risk of shorting in the long runs, although I haven't looked into it enough to know exactly how it is addressed.

Craig SN68


---In amelyachtowners@yahoogroups.com, wrote :

Craig , Your original post seemed to support locating breakers far from the power source , however this post seems to acknowledge the protection offered by locating breakers as close as possible to the battery bank. You even pointed to boat that burned up cables as a result of a short . Now I must be missing something . When I build a house , I have 220v/ 200 amps coming through a  wall , I locate the distribution panel as close as possible to where it comes thru the wall. The ele ctric immediately goes thru appropriate size breakers and passes thru appropriate sized wiring on to  outlets ,  pumps ,etc . In the event of a short there is little chance of the wire being overloaded . You do not use 14g wire with a 20 amp breaker ! In a house you would not run a 220v line to a laundry room and place the breaker on the wall behind the dryer. I have never understood the difference between protecting a boat vs. a house . But , maybe I am missing something, it would not be the first time.
Pat
SM #123


-----Original Message-----
From: sangaris@... [amelyachtowners] <amelyachtowners@yahoogroups.com>
To: amelyachtowners <amelyachtowners@yahoogroups.com>
Sent: Mon, Oct 16, 2017 9:34 am
Subject: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 
Alan,
That seems an excellent idea. I remember that in 2001 I totally redid SM Miss Lindy's wiring (don't recall the hull number) after it completely burned out for the third time. All the heavy cables in the engine room, from battery to starter to generator to main house feeds had melted solid. As I finished up I still had low volts from the engine to the battery.  Traced it to the starting cables having chaffed about 12 inches down inside the PVC pipe from the battery to the engine (that was supposedly there to prevent chafe). Your solution would have prevented much heartache and expense. 
Will be interested in Bill K's bounce. Perhaps the modern distributed systems do incorporate that.
Craig SN#68

---In amelyachtowners@yahoogroups.com, wrote :

well said Bill,
BUT that's exactly what we have on our SMs....th e anchor windlass, the genoa furler etc have the breakers at the "other end" of the cables that run from the house bank...and...on the standard setup, there are NO FUSES near the battery connections. 
I've put large Blue Sea fuses in the battery compartment on each of my 3 banks of 4 6V series batteries to try to address these issues.
What have you done ?
Cheers
Alan
Elyse SM437

Craig,

I think you (and Amel in the "old days") are simply missing the point of circuit breakers.  They are most certainly NOT there to protect the anchor washdown pump, or t he thruster motor, or any other piece of equipment.  There is nothing a circuit breaker can do to "protect" the pump motor, or other device:  If it shorts, it has already died! If, in normal operation, it draws too much current for the wiring to support, then the wiring is undersized.

Circuit breakers are there to protect the WIRING and prevent the catastrophic results that can occur if a short occurs ANYWHERE that overloads the wiring.  This can occur from many faults, none of them likely, but all with disastrous consequences.  Wire chafe is probably the most common cause on boats, but others happen. I'd guess loose connections are a close second.  

Having a breaker at the far end of the wire, away from the battery, completely misses the point of why it is there in the first place. In my opinion, if you have a circuit breaker at the point of use of the power, you might as well just replace it with a switch--it is essentially useless. 

When I ran a service department for a large charter company, one of the annual safety meetings I ran for for my staff was to dead short circuit a 12 volt battery through 14 gauge wire.  Watching solid copper wire burst into flame and literally explode was a sobering experience for people who could easily get into the habit of thinking "its only 12 volts." It really made the point about why fuses and circuit breakers were essential.

There is nothing at all wrong with distributed CONTROL of an electrical system. That is just fancy electronics.  But... you can not "distribute" protection of the wiring. I have never heard a  good reason to run long lengths of un-fused wiring on a boat--or anywhere else.  It is just dangerous--and for absolutely no benefit.  Dangerous overloads rarely occur because of equipment problems.  They occur because of wiring faults.  Do they happen often?  No, not at all. But when they do, it is truly terrifying.  

C-zone, Ocotplex, etc, a re NOT wiring protection systems.  They are not "circuit breakers".  They are CONTROL systems.  Very different animals.

I have seen several boat fires at much closer quarters than I ever hope to repeat, and most of them were electrical in origin, all from things that shouldn't have happened--but did.  

Bill Kinney
Sm160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@yahoogroups.com, wrote :

I'd always thought Amel was ahead of the curve with its Distributed Electrical System. That seems to be the direction the industry is going, now with solid state circuit breakers controlled through the NMEA2000 data network. Eliminates the large industrial style circuit breaker panels of yore and adds great flexibility. Check out CAPI2, C-Zone, Octoplex, etc. Seems Amel is going backwards technologically if they're centralizing. Let's see, your anchor washdown pump shorts and rather than it tripping an adjacent breaker it's got to overload a 15 meter long cable run back to the central circuit breaker panel. To say nothing of the excess wiring to give all equipment a "home run". Must be missing something in this discussion.
Cheers, Craig SN68 Sangaris
< br>


Mark Erdos
 

Amen Brother!!!

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff - SM2K - #275

Currently cruising - Grenada

www.creampuff.us

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Tuesday, October 17, 2017 11:16 AM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 

 

Bill K and Pat,

 

I would never say that "I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs."

 

I would not say anything like that for numerous reasons. I think you know why.

 

Since Henri Amel is not here to defend his decisions made many years ago, I will remind everyone that at the time these decisions were made they very likely conformed 100% with the regulations in force in Europe and conformed with the thinking at the time. Let's compare Henri Amel's engineering decisions to General Motors at the same time:

- Disintegrating plastic bumper parts

- 4-6-8 engines with 100% failure

- Gasoline to Diesel conversions with almost 100% failure

- Reduction of plasticides in paint which caused paint to fade in 6 years

- Plastic transmission parts which caused a new industry to emerge to repair transmissions

- Fiero & Corvair (one name says it all)

- Foam headliners which fell in 5 years

- Chrome coated plastic which lasted about 2 years

on, and on, and on.

 

Can one improve on yesterday's technology? Certainly! 

Can one not understand decisions made yesterday? Absolutely!

Should one of us criticize Henri Amel? Never!

 

Anyway, this is my sermon for the month. I hope that you enjoyed it. 

 

Best,

 

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  
http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970

 

 

 

 

 

On Tue, Oct 17, 2017 at 8:39 AM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Hi Pat, 

Yes, that's why I thought Alan's adding the Blue Sea fuses at the batteries sounded wise. Btw, in my house the distribution panel is smack in the middle of the house which reduces the total amount of wiring. It does, of course, have a main service breaker at the external drop wire, analogous to Alan's Blue Sea fuse. Then there are separate fused disconnects adjacent to heavy loads like the A/C and hot water heater in addition to breakers for those at the distribution panel.

 

I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs. Alan seems to have a good solution.  And, while the new Amel centralized panel would meet Bill K's criterion, it is (likely) not fused close to the batteries, leaving the same risk of chafe and shorting in either the wires going to the panel or the wires going to the engine & generator starting motors.

 

I do suspect that the industry will continue to modernize with Distributed electric systems and have not overlooked the risk of shorting in the long runs, although I haven't looked into it enough to know exactly how it is addressed.

 

Craig SN68



---In amelyachtowners@..., wrote :

Craig , Your original post seemed to support locating breakers far from the power source , however this post seems to acknowledge the protection offered by locating breakers as close as possible to the battery bank. You even pointed to boat that burned up cables as a result of a short . Now I must be missing something . When I build a house , I have 220v/ 200 amps coming through a  wall , I locate the distribution panel as close as possible to where it comes thru the wall. The ele ctric immediately goes thru appropriate size breakers and passes thru appropriate sized wiring on to  outlets ,  pumps ,etc . In the event of a short there is little chance of the wire being overloaded . You do not use 14g wire with a 20 amp breaker ! In a house you would not run a 220v line to a laundry room and place the breaker on the wall behind the dryer. I have never understood the difference between protecting a boat vs. a house . But , maybe I am missing something, it would not be the first time.

Pat

SM #123

-----Original Message-----
From: sangaris@... [amelyachtowners] <amelyachtowners@...>
To: amelyachtowners <amelyachtowners@...>
Sent: Mon, Oct 16, 2017 9:34 am
Subject: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 

Alan,

That seems an excellent idea. I remember that in 2001 I totally redid SM Miss Lindy's wiring (don't recall the hull number) after it completely burned out for the third time. All the heavy cables in the engine room, from battery to starter to generator to main house feeds had melted solid. As I finished up I still had low volts from the engine to the battery.  Traced it to the starting cables having chaffed about 12 inches down inside the PVC pipe from the battery to the engine (that was supposedly there to prevent chafe). Your solution would have prevented much heartache and expense. 

Will be interested in Bill K's bounce. Perhaps the modern distributed systems do incorporate that.

Craig SN#68


---In amelyachtowners@..., wrote :

well said Bill,

BUT that's exactly what we have on our SMs....th e anchor windlass, the genoa furler etc have the breakers at the "other end" of the cables that run from the house bank...and...on the standard setup, there are NO FUSES near the battery connections. 

I've put large Blue Sea fuses in the battery compartment on each of my 3 banks of 4 6V series batteries to try to address these issues.

What have you done ?

Cheers

Alan

Elyse SM437

 

Craig,

 

I think you (and Amel in the "old days") are simply missing the point of circuit breakers.  They are most certainly NOT there to protect the anchor washdown pump, or t he thruster motor, or any other piece of equipment.  There is nothing a circuit breaker can do to "protect" the pump motor, or other device:  If it shorts, it has already died! If, in normal operation, it draws too much current for the wiring to support, then the wiring is undersized.

 

Circuit breakers are there to protect the WIRING and prevent the catastrophic results that can occur if a short occurs ANYWHERE that overloads the wiring.  This can occur from many faults, none of them likely, but all with disastrous consequences.  Wire chafe is probably the most common cause on boats, but others happen. I'd guess loose connections are a close second.  

 

Having a breaker at the far end of the wire, away from the battery, completely misses the point of why it is there in the first place. In my opinion, if you have a circuit breaker at the point of use of the power, you might as well just replace it with a switch--it is essentially useless. 

 

When I ran a service department for a large charter company, one of the annual safety meetings I ran for for my staff was to dead short circuit a 12 volt battery through 14 gauge wire.  Watching solid copper wire burst into flame and literally explode was a sobering experience for people who could easily get into the habit of thinking "its only 12 volts." It really made the point about why fuses and circuit breakers were essential.

 

There is nothing at all wrong with distributed CONTROL of an electrical system. That is just fancy electronics.  But... you can not "distribute" protection of the wiring. I have never heard a  good reason to run long lengths of un-fused wiring on a boat--or anywhere else.  It is just dangerous--and for absolutely no benefit.  Dangerous overloads rarely occur because of equipment problems.  They occur because of wiring faults.  Do they happen often?  No, not at all. But when they do, it is truly terrifying.  

 

C-zone, Ocotplex, etc, a re NOT wiring protection systems.  They are not "circuit breakers".  They are CONTROL systems.  Very different animals.

 

I have seen several boat fires at much closer quarters than I ever hope to repeat, and most of them were electrical in origin, all from things that shouldn't have happened--but did.  

 

Bill Kinney

Sm160, Harmonie

Back Creek, Annapolis, MD

 

 



---In amelyachtowners@..., wrote :

I'd always thought Amel was ahead of the curve with its Distributed Electrical System. That seems to be the direction the industry is going, now with solid state circuit breakers controlled through the NMEA2000 data network. Eliminates the large industrial style circuit breaker panels of yore and adds great flexibility. Check out CAPI2, C-Zone, Octoplex, etc. Seems Amel is going backwards technologically if they're centralizing. Let's see, your anchor washdown pump shorts and rather than it tripping an adjacent breaker it's got to overload a 15 meter long cable run back to the central circuit breaker panel. To say nothing of the excess wiring to give all equipment a "home run". Must be missing something in this discussion.

Cheers, Craig SN68 Sangaris

< br>

 

Mike Johnson
 

Agree entirely with Bill R’s comments.

We have never found any defect with Henri Amel’s basic concept or workmanship on the SM2K.

The only problems we have faced is where others have attempted ‘fixes’ to the original specifications.

Very best wishes 

Mike & Peta

Solitude
SM2K 461

On 17 Oct 2017, at 17:11, 'Mark Erdos' mcerdos@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Amen Brother!!!

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff - SM2K - #275

Currently cruising - Grenada

www.creampuff.us

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Tuesday, October 17, 2017 11:16 AM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 

 

Bill K and Pat,

 

I would never say that "I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs."

 

I would not say anything like that for numerous reasons. I think you know why.

 

Since Henri Amel is not here to defend his decisions made many years ago, I will remind everyone that at the time these decisions were made they very likely conformed 100% with the regulations in force in Europe and conformed with the thinking at the time. Let's compare Henri Amel's engineering decisions to General Motors at the same time:

- Disintegrating plastic bumper parts

- 4-6-8 engines with 100% failure

- Gasoline to Diesel conversions with almost 100% failure

- Reduction of plasticides in paint which caused paint to fade in 6 years

- Plastic transmission parts which caused a new industry to emerge to repair transmissions

- Fiero & Corvair (one name says it all)

- Foam headliners which fell in 5 years

- Chrome coated plastic which lasted about 2 years

on, and on, and on.

 

Can one improve on yesterday's technology? Certainly! 

Can one not understand decisions made yesterday? Absolutely!

Should one of us criticize Henri Amel? Never!

 

Anyway, this is my sermon for the month. I hope that you enjoyed it. 

 

Best,

 

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  
http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970

 

 

 

 

 

On Tue, Oct 17, 2017 at 8:39 AM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Hi Pat, 

Yes, that's why I thought Alan's adding the Blue Sea fuses at the batteries sounded wise. Btw, in my house the distribution panel is smack in the middle of the house which reduces the total amount of wiring. It does, of course, have a main service breaker at the external drop wire, analogous to Alan's Blue Sea fuse. Then there are separate fused disconnects adjacent to heavy loads like the A/C and hot water heater in addition to breakers for those at the distribution panel.

 

I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs. Alan seems to have a good solution.  And, while the new Amel centralized panel would meet Bill K's criterion, it is (likely) not fused close to the batteries, leaving the same risk of chafe and shorting in either the wires going to the panel or the wires going to the engine & generator starting motors.

 

I do suspect that the industry will continue to modernize with Distributed electric systems and have not overlooked the risk of shorting in the long runs, although I haven't looked into it enough to know exactly how it is addressed.

 

Craig SN68



---In amelyachtowners@..., wrote :

Craig , Your original post seemed to support locating breakers far from the power source , however this post seems to acknowledge the protection offered by locating breakers as close as possible to the battery bank. You even pointed to boat that burned up cables as a result of a short . Now I must be missing something . When I build a house , I have 220v/ 200 amps coming through a  wall , I locate the distribution panel as close as possible to where it comes thru the wall. The ele ctric immediately goes thru appropriate size breakers and passes thru appropriate sized wiring on to  outlets ,  pumps ,etc . In the event of a short there is little chance of the wire being overloaded . You do not use 14g wire with a 20 amp breaker ! In a house you would not run a 220v line to a laundry room and place the breaker on the wall behind the dryer. I have never understood the difference between protecting a boat vs. a house . But , maybe I am missing something, it would not be the first time.

Pat

SM #123

-----Original Message-----
From: sangaris@... [amelyachtowners] <amelyachtowners@...>
To: amelyachtowners <amelyachtowners@...>
Sent: Mon, Oct 16, 2017 9:34 am
Subject: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 

Alan,

That seems an excellent idea. I remember that in 2001 I totally redid SM Miss Lindy's wiring (don't recall the hull number) after it completely burned out for the third time. All the heavy cables in the engine room, from battery to starter to generator to main house feeds had melted solid. As I finished up I still had low volts from the engine to the battery.  Traced it to the starting cables having chaffed about 12 inches down inside the PVC pipe from the battery to the engine (that was supposedly there to prevent chafe). Your solution would have prevented much heartache and expense. 

Will be interested in Bill K's bounce. Perhaps the modern distributed systems do incorporate that.

Craig SN#68


---In amelyachtowners@..., wrote :

well said Bill,

BUT that's exactly what we have on our SMs....th e anchor windlass, the genoa furler etc have the breakers at the "other end" of the cables that run from the house bank...and...on the standard setup, there are NO FUSES near the battery connections. 

I've put large Blue Sea fuses in the battery compartment on each of my 3 banks of 4 6V series batteries to try to address these issues.

What have you done ?

Cheers

Alan

Elyse SM437

 

Craig,

 

I think you (and Amel in the "old days") are simply missing the point of circuit breakers.  They are most certainly NOT there to protect the anchor washdown pump, or t he thruster motor, or any other piece of equipment.  There is nothing a circuit breaker can do to "protect" the pump motor, or other device:  If it shorts, it has already died! If, in normal operation, it draws too much current for the wiring to support, then the wiring is undersized.

 

Circuit breakers are there to protect the WIRING and prevent the catastrophic results that can occur if a short occurs ANYWHERE that overloads the wiring.  This can occur from many faults, none of them likely, but all with disastrous consequences.  Wire chafe is probably the most common cause on boats, but others happen. I'd guess loose connections are a close second.  

 

Having a breaker at the far end of the wire, away from the battery, completely misses the point of why it is there in the first place. In my opinion, if you have a circuit breaker at the point of use of the power, you might as well just replace it with a switch--it is essentially useless. 

 

When I ran a service department for a large charter company, one of the annual safety meetings I ran for for my staff was to dead short circuit a 12 volt battery through 14 gauge wire.  Watching solid copper wire burst into flame and literally explode was a sobering experience for people who could easily get into the habit of thinking "its only 12 volts." It really made the point about why fuses and circuit breakers were essential.

 

There is nothing at all wrong with distributed CONTROL of an electrical system. That is just fancy electronics.  But... you can not "distribute" protection of the wiring. I have never heard a  good reason to run long lengths of un-fused wiring on a boat--or anywhere else.  It is just dangerous--and for absolutely no benefit.  Dangerous overloads rarely occur because of equipment problems.  They occur because of wiring faults.  Do they happen often?  No, not at all. But when they do, it is truly terrifying.  

 

C-zone, Ocotplex, etc, a re NOT wiring protection systems.  They are not "circuit breakers".  They are CONTROL systems.  Very different animals.

 

I have seen several boat fires at much closer quarters than I ever hope to repeat, and most of them were electrical in origin, all from things that shouldn't have happened--but did.  

 

Bill Kinney

Sm160, Harmonie

Back Creek, Annapolis, MD

 

 



---In amelyachtowners@..., wrote :

I'd always thought Amel was ahead of the curve with its Distributed Electrical System. That seems to be the direction the industry is going, now with solid state circuit breakers controlled through the NMEA2000 data network. Eliminates the large industrial style circuit breaker panels of yore and adds great flexibility. Check out CAPI2, C-Zone, Octoplex, etc. Seems Amel is going backwards technologically if they're centralizing. Let's see, your anchor washdown pump shorts and rather than it tripping an adjacent breaker it's got to overload a 15 meter long cable run back to the central circuit breaker panel. To say nothing of the excess wiring to give all equipment a "home run". Must be missing something in this discussion.

Cheers, Craig SN68 Sangaris

< br>

 

Craig & Katherine Briggs SN 68 Sangaris Tropic Isle Harbor, FL
 

Well, whatever spin you want to put on it, Alan's point that the battery cables should be protected close to the batteries, before they run through the boat and pose a fire hazard, is a good one. 
Cheers,
Craig SN68


---In amelyachtowners@..., <mike.k.johnson@...> wrote :

Agree entirely with Bill R’s comments.

We have never found any defect with Henri Amel’s basic concept or workmanship on the SM2K.

The only problems we have faced is where others have attempted ‘fixes’ to the original specifications.

Very best wishes 

Mike & Peta

Solitude
SM2K 461

On 17 Oct 2017, at 17:11, 'Mark Erdos' mcerdos@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Amen Brother!!!

 

 

With best regards,

 

Mark

 

Skipper

Sailing Vessel - Cream Puff - SM2K - #275

Currently cruising - Grenada

www.creampuff.us

 

From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Tuesday, October 17, 2017 11:16 AM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 

 

Bill K and Pat,

 

I would never say that "I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs."

 

I would not say anything like that for numerous reasons. I think you know why.

 

Since Henri Amel is not here to defend his decisions made many years ago, I will remind everyone that at the time these decisions were made they very likely conformed 100% with the regulations in force in Europe and conformed with the thinking at the time. Let's compare Henri Amel's engineering decisions to General Motors at the same time:

- Disintegrating plastic bumper parts

- 4-6-8 engines with 100% failure

- Gasoline to Diesel conversions with almost 100% failure

- Reduction of plasticides in paint which caused paint to fade in 6 years

- Plastic transmission parts which caused a new industry to emerge to repair transmissions

- Fiero & Corvair (one name says it all)

- Foam headliners which fell in 5 years

- Chrome coated plastic which lasted about 2 years

on, and on, and on.

 

Can one improve on yesterday's technology? Certainly! 

Can one not understand decisions made yesterday? Absolutely!

Should one of us criticize Henri Amel? Never!

 

Anyway, this is my sermon for the month. I hope that you enjoyed it. 

 

Best,

 

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  
http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970

 

 

 

 

 

On Tue, Oct 17, 2017 at 8:39 AM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:

 

Hi Pat, 

Yes, that's why I thought Alan's adding the Blue Sea fuses at the batteries sounded wise. Btw, in my house the distribution panel is smack in the middle of the house which reduces the total amount of wiring. It does, of course, have a main service breaker at the external drop wire, analogous to Alan's Blue Sea fuse. Then there are separate fused disconnects adjacent to heavy loads like the A/C and hot water heater in addition to breakers for those at the distribution panel.

 

I think Bill K's point is that he thinks Capt. Henri's original engineering was poorly done and left an unsafe condition with unprotected long wire runs. Alan seems to have a good solution.  And, while the new Amel centralized panel would meet Bill K's criterion, it is (likely) not fused close to the batteries, leaving the same risk of chafe and shorting in either the wires going to the panel or the wires going to the engine & generator starting motors.

 

I do suspect that the industry will continue to modernize with Distributed electric systems and have not overlooked the risk of shorting in the long runs, although I haven't looked into it enough to know exactly how it is addressed.

 

Craig SN68



---In amelyachtowners@..., <sailw32@...> wrote :

Craig , Your original post seemed to support locating breakers far from the power source , however this post seems to acknowledge the protection offered by locating breakers as close as possible to the battery bank. You even pointed to boat that burned up cables as a result of a short . Now I must be missing something . When I build a house , I have 220v/ 200 amps coming through a  wall , I locate the distribution panel as close as possible to where it comes thru the wall. The ele ctric immediately goes thru appropriate size breakers and passes thru appropriate sized wiring on to  outlets ,  pumps ,etc . In the event of a short there is little chance of the wire being overloaded . You do not use 14g wire with a 20 amp breaker ! In a house you would not run a 220v line to a laundry room and place the breaker on the wall behind the dryer. I have never understood the difference between protecting a boat vs. a house . But , maybe I am missing something, it would not be the first time.

Pat

SM #123

-----Original Message-----
From: sangaris@... [amelyachtowners] <amelyachtowners@...>
To: amelyachtowners <amelyachtowners@...>
Sent: Mon, Oct 16, 2017 9:34 am
Subject: [Amel Yacht Owners] Re: Distributed vs. Conventional Electrical Systems

 

Alan,

That seems an excellent idea. I remember that in 2001 I totally redid SM Miss Lindy's wiring (don't recall the hull number) after it completely burned out for the third time. All the heavy cables in the engine room, from battery to starter to generator to main house feeds had melted solid. As I finished up I still had low volts from the engine to the battery.  Traced it to the starting cables having chaffed about 12 inches down inside the PVC pipe from the battery to the engine (that was supposedly there to prevent chafe). Your solution would have prevented much heartache and expense. 

Will be interested in Bill K's bounce. Perhaps the modern distributed systems do incorporate that.

Craig SN#68


---In amelyachtowners@..., <divanz620@...> wrote :

well said Bill,

BUT that's exactly what we have on our SMs....th e anchor windlass, the genoa furler etc have the breakers at the "other end" of the cables that run from the house bank...and...on the standard setup, there are NO FUSES near the battery connections. 

I've put large Blue Sea fuses in the battery compartment on each of my 3 banks of 4 6V series batteries to try to address these issues.

What have you done ?

Cheers

Alan

Elyse SM437

 

Craig,

 

I think you (and Amel in the "old days") are simply missing the point of circuit breakers.  They are most certainly NOT there to protect the anchor washdown pump, or t he thruster motor, or any other piece of equipment.  There is nothing a circuit breaker can do to "protect" the pump motor, or other device:  If it shorts, it has already died! If, in normal operation, it draws too much current for the wiring to support, then the wiring is undersized.

 

Circuit breakers are there to protect the WIRING and prevent the catastrophic results that can occur if a short occurs ANYWHERE that overloads the wiring.  This can occur from many faults, none of them likely, but all with disastrous consequences.  Wire chafe is probably the most common cause on boats, but others happen. I'd guess loose connections are a close second.  

 

Having a breaker at the far end of the wire, away from the battery, completely misses the point of why it is there in the first place. In my opinion, if you have a circuit breaker at the point of use of the power, you might as well just replace it with a switch--it is essentially useless. 

 

When I ran a service department for a large charter company, one of the annual safety meetings I ran for for my staff was to dead short circuit a 12 volt battery through 14 gauge wire.  Watching solid copper wire burst into flame and literally explode was a sobering experience for people who could easily get into the habit of thinking "its only 12 volts." It really made the point about why fuses and circuit breakers were essential.

 

There is nothing at all wrong with distributed CONTROL of an electrical system. That is just fancy electronics.  But... you can not "distribute" protection of the wiring. I have never heard a  good reason to run long lengths of un-fused wiring on a boat--or anywhere else.  It is just dangerous--and for absolutely no benefit.  Dangerous overloads rarely occur because of equipment problems.  They occur because of wiring faults.  Do they happen often?  No, not at all. But when they do, it is truly terrifying.  

 

C-zone, Ocotplex, etc, a re NOT wiring protection systems.  They are not "circuit breakers".  They are CONTROL systems.  Very different animals.

 

I have seen several boat fires at much closer quarters than I ever hope to repeat, and most of them were electrical in origin, all from things that shouldn't have happened--but did.  

 

Bill Kinney

Sm160, Harmonie

Back Creek, Annapolis, MD

 

 



---In amelyachtowners@..., <sangaris@...> wrote :

I'd always thought Amel was ahead of the curve with its Distributed Electrical System. That seems to be the direction the industry is going, now with solid state circuit breakers controlled through the NMEA2000 data network. Eliminates the large industrial style circuit breaker panels of yore and adds great flexibility. Check out CAPI2, C-Zone, Octoplex, etc. Seems Amel is going backwards technologically if they're centralizing. Let's see, your anchor washdown pump shorts and rather than it tripping an adjacent breaker it's got to overload a 15 meter long cable run back to the central circuit breaker panel. To say nothing of the excess wiring to give all equipment a "home run". Must be missing something in this discussion.

Cheers, Craig SN68 Sangaris

< br>

 

Bill & Judy Rouse <yahoogroups@...>
 

Craig,

I agree with Alan's point and before we sold BeBe I had decided to place 6 of the Blue Sea 5191 MRBF Terminal Fuse Blocks with a removeable Blue Sea BS5185 (150A) amp fuse on each of the 6 positive battery pairs on the positive post  of the battery and connect the the positive lead for each pair to the newly installed terminal block fuse. My assumption was that the 500 amp bow thruster would not burn individual 150 amp fuses...I may be wrong on this. The fuses are available from 50 amps to 300 amps. Since the fuses are replaceable, I was going to buy extras.

Of course, I have not tested this, so I cannot say that it works and/or whether it is the best solution.


Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970

James Alton
 

Bill,

   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did not leak at all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will consider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220

On Oct 18, 2017, at 12:21 PM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@...> wrote:

Craig,

I agree with Alan's point and before we sold BeBe I had decided to place 6 of the Blue Sea 5191 MRBF Terminal Fuse Blocks with a removeable Blue Sea BS5185 (150A) amp fuse on each of the 6 positive battery pairs on the positive post  of the battery and connect the the positive lead for each pair to the newly installed terminal block fuse. My assumption was that the 500 amp bow thruster would not burn individual 150 amp fuses...I may be wrong on this. The fuses are available from 50 amps to 300 amps. Since the fuses are replaceable, I was going to buy extras.

Of course, I have not tested this, so I cannot say that it works and/or whether it is the best solution.

Ryan Meador
 

I believe you're supposed to fuse the battery bank as a whole, and not individual batteries.  That means one fuse for the whole bank.  The reason for this is that some subset of the fuses could blow (one could be slightly more sensitive, or one battery might supply slightly more current under load) and you wouldn't know.  You would hope that a cascading failure causes them all to blow, but it won't necessarily.  And this is bad because now you have one or more batteries isolated from the rest of the bank, yet you still have power, so you're probably not going to go look under the bunk to check the fuses.  With your battery bank now smaller than you think it is, you're likely to discharge it deeper than you intend, and the isolated battery won't be getting charged... quickly all the batteries will be ruined.

I'm a big fan of those battery terminal fuses Bill mentioned.  I installed them on my old boat after reading this excellent article (that whole site is fantastic).  I'm going to do something similar on my SM as soon as I figure out what the current rating should be; it might be possible to get away with a 300A fuse since they don't blow instantly.  As long as we're not leaning on the thruster or windlass switch for too long, I think it would be OK, but I'd love more info about the actual current draw of these systems.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA

On Wed, Oct 18, 2017 at 12:53 PM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Bill,


   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did not leak at all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will consider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220
On Oct 18, 2017, at 12:21 PM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:

Craig,

I agree with Alan's point and before we sold BeBe I had decided to place 6 of the Blue Sea 5191 MRBF Terminal Fuse Blocks with a removeable Blue Sea BS5185 (150A) amp fuse on each of the 6 positive battery pairs on the positive post  of the battery and connect the the positive lead for each pair to the newly installed terminal block fuse. My assumption was that the 500 amp bow thruster would not burn individual 150 amp fuses...I may be wrong on this. The fuses are available from 50 amps to 300 amps. Since the fuses are replaceable, I was going to buy extras.

Of course, I have not tested this, so I cannot say that it works and/or whether it is the best solution.


Bill & Judy Rouse <yahoogroups@...>
 

James,

From the Super Maramu 2000 Owners Manual...it states 7,000 watts or 510 amps

Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970



On Wed, Oct 18, 2017 at 11:53 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Bill,


   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did not leak at all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will con sider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220
On Oct 18, 2017, at 12:21 PM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:

Craig,

I agree with Alan's point and before we sold BeBe I had decided to place 6 of the Blue Sea 5191 MRBF Terminal Fuse Blocks with a removeable Blue Sea BS5185 (150A) amp fuse on each of the 6 positive battery pairs on the positive post  of the battery and connect the the positive lead for each pair to the newly installed terminal block fuse. My assumption was that the 500 amp bow thrust er would not burn individual 150 amp fuses...I may be wrong on this. The fuses are available from 50 amps to 300 amps. Since the fuses are replaceable, I was going to buy extras.

Of course, I have not tested this, so I cannot say that it works and/or whether it is the best solution.


greatketch@...
 

What calculation did you do to convert 7000 Watts to 510 Amps?

P= V * A
510 Amps at 24 Volts = 12,000 Watts??

For what it is worth, the name plate on the motor on my older Super Maramu (they might not all be the same) is 6.3kW

To get a good number, for current draw you can't assume 24 Volts.  When you are drawing that much power, the voltage will drop, a lot.

For really high power draws like this, it is not unreasonable to assume as low as 18 Volts.

6,300 Watts/18 Volts = 350 Amps

If we do go with a 7000 watt rating, that's still "only" 388 amps.  A perfectly reasonable number to protect with a 500 Amp fuse.


Bill Kinney
SM160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@..., <yahoogroups@...> wrote :

James,

From the Super Maramu 2000 Owners Manual...it states 7,000 watts or 510 amps

Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  http://www.amelschool. com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970



On Wed, Oct 18, 2017 at 11:53 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Bill,


   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did not leak at all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will con sider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220

greatketch@...
 

Ryan,

I considered the scenario you describe, and decided it is not a worry for a couple of reasons. I agree it is a theoretical concern, but not a practical one.

First, if I am drawing significantly different amperages from my 4 parallel pairs of batteries then I have very serious other problems that will kill the batteries quickly because of mismatched charge/discharge profiles that have nothing to do with the fuses.

If I am drawing power close to the maximum carrying capacity of the fuse, of course one will blow first.  But then the power draw from the other three immediately jumps by 33%.  For fuses already on the edge, that will surely cause a very fast failure.  It is POSSIBLE, but very unlikely, that the power would be shut off before the failure cascades to the other batteries. In the case of the kind of short circuit I am actually trying to protect against, of course there is not a shut off option.

Finally, as fuses age, they can sometimes fail below their rated capacity.  This is, I believe, the most likely way I could lose one fuse and not the others.

If one fuse was to fail, and I lost 25% of my battery capacity, I would very quickly notice that by the way I monitor my battery charge/discharge cycles.  That is exactly the kind of problem I am always on the look out for because it could indicated a shorted cell in one of the batteries.  A potentially dangerous situation I would very much like to know about if it happens.

The other problem I have found, is getting a fuse rated to interrupt 500 DC AMPS in one package gets rather difficult, and expensive.

Bill Kinney
SM160, Harmonie
Back Creek, Annapolis, MD

Bill & Judy Rouse <yahoogroups@...>
 

Bill Kinney,

I assume that you must be asking your question to Amel, because Amel is the one that published the Super Maramu 2000 Owners Manual (page attached). 

Amps = Watts/Volts. 
Watts = Amps x Volts

So, either Amel is wrong with Watts or Amps, or both. 

Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970

On Wed, Oct 18, 2017 at 2:16 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:
 

What calculation did you do to convert 7000 Watts to 510 Amps?

P= V * A
510 Amps at 24 Volts = 12,000 Watts??

For what it is worth, the name plate on the motor on my older Super Maramu (they might not all be the same) is 6.3kW

To get a good number, for current draw you can't assume 24 Volts.  When you are drawing that much power, the voltage will drop, a lot.

For really high power draws like this, it is not unreasonable to assume as low as 18 Volts.

6,300 Watts/18 Volts = 350 Amps

If we do go with a 7000 watt rating, that's still "only" 388 amps.  A perfectly reasonable number to protect with a 500 Amp fuse.


Bill Kinney
SM160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@yahoogroups.com, wrote :

James,

From the Super Maramu 20 00 Owners Manual...it states 7,000 watts or 510 amps
Inline image 1
Best,



On Wed, Oct 18, 2017 at 11:53 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:
 

Bill,


   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did not leak a t all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will con sider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220


James Alton
 

Bill,

   Thanks for showing where you got the 500 amps from.  I am still confused about what the table is trying to tell us exactly.  I note that there are two columns, one is labeled amperage and the other is “Amperage on load” which I am guessing might mean “Amperage under load”.  

   Congratulations on the success of your school and for publishing your book.  Does your book cover all of the Amel models or is it mainly for the SM?

   Your absence on the boards will be missed by myself and I am sure others.  Best of luck with your endeavours.

James Alton
SV,  Sueno,  Maramu #220

On Oct 18, 2017, at 4:35 PM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@...> wrote:


Bill Kinney,

I assume that you must be asking your question to Amel, because Amel is the one that published the Super Maramu 2000 Owners Manual (page attached). 

Amps = Watts/Volts. 
Watts = Amps x Volts

So, either Amel is wrong with Watts or Amps, or both. 

Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus
Amel School  http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970

On Wed, Oct 18, 2017 at 2:16 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:
 

What calculation did you do to convert 7000 Watts to 510 Amps?

P= V * A
510 Amps at 24 Volts = 12,000 Watts??

For what it is worth, the name plate on the motor on my older Super Maramu (they might not all be the same) is 6.3kW

To get a good number, for current draw you can't assume 24 Volts.  When you are drawing that much power, the voltage will drop, a lot.

For really high power draws like this, it is not unreasonable to assume as low as 18 Volts.

6,300 Watts/18 Volts = 350 Amps

If we do go with a 7000 watt rating, that's still "only" 388 amps.  A perfectly reasonable number to protect with a 500 Amp fuse.


Bill Kinney
SM160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@yahoogroups.com, wrote :

James,

From the Super Maramu 20 00 Owners Manual...it states 7,000 watts or 510 amps
Inline image 1
Best,



On Wed, Oct 18, 2017 at 11:53 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:
 

Bill,


   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did not leak a t all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will con sider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220





James Alton
 

Bill Kinney,

   Good point about the voltage drop. I measured mine as dropping from 13.5 (charger was on so this was not an accurate test) to about 11.75 after a 5 second burst. 

   Does the SM have a breaker for the bow thruster and if so can you tell me the amperage?   I guess that the 6.3KW rating doesn’t tell us much since we don’t know how loaded the motor is.  

   Also, can someone tell me about how much free play is normal for a bow thruster?  I can rock the prop on my thruster back and forth about 3/16” without any resistance as measured from the tips of the blades.  The output shaft does not seem to have any play in it’s bearing so I assume that what I am feeling is the gear lash plus any play in the shaft to motor splines.

James Alton
SV Sueno,  Maramu #220

On Oct 18, 2017, at 4:16 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:


What calculation did you do to convert 7000 Watts to 510 Amps?

P= V * A
510 Amps at 24 Volts = 12,000 Watts??

For what it is worth, the name plate on the motor on my older Super Maramu (they might not all be the same) is 6.3kW

To get a good number, for current draw you can't assume 24 Volts.  When you are drawing that much power, the voltage will drop, a lot.

For really high power draws like this, it is not unreasonable to assume as low as 18 Volts.

6,300 Watts/18 Volts = 350 Amps

If we do go with a 7000 watt rating, that's still "only" 388 amps.  A perfectly reasonable number to protect with a 500 Amp fuse.


Bill Kinney
SM160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@..., wrote :

James,

From the Super Maramu 2000 Owners Manual...it states 7,000 watts or 510 amps

Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus
Amel School  http://www.amelschool. com
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970



On Wed, Oct 18, 2017 at 11:53 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Bill,


   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did no t leak at all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will con sider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220



Ryan Meador
 

Bill K: I agree that it is a mostly theoretical concern, but you know the difference between theory and practice, right? :D  My own knowledge and sources that I trust lead me to err on the side of the simpler system, even if it is harder to source the correct fuses.

Regarding the bow thruster power: I think we have to take everything in that table with a grain of salt because none of the wattages match up with the amperages.  I think they're trying to convey something other than a strict electrical relationship between those numbers.  I wonder if the 510A value might be the inrush current, and the 7kW the continuous power?  I agree with James that "Amperage on load" probably means "under load", but implies the "amperage" column is no-load, so why aren't more of the values in the "on load" column?  The bow thruster is in essence always under load.  Another possibility is the thruster input power is ~9180W (510A * 18V), the output is 7000W, and thus the efficiency is a paltry 76%.  Does anyone have a clamp-on ammeter that would be willing to do some science (I don't trust the battery monitor to react quickly enough to get a reliable inrush current measurement)?

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA

On Wed, Oct 18, 2017 at 4:38 PM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Bill,


   Thanks for showing where you got the 500 amps from.  I am still confused about what the table is trying to tell us exactly.  I note that there are two columns, one is labeled amperage and the other is “Amperage on load” which I am guessing might mean “Amperage under load”.  

   Congratulations on the success of your school and for publishing your book.  Does your book cover all of the Amel models or is it mainly for the SM?

   Your absence on the boards will be missed by myself and I am sure others.  Best of luck with your endeavours.

James Alton
SV,  Sueno,  Maramu #220
On Oct 18, 2017, at 4:35 PM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:


Bill Kinney,

I assume that you must be asking your question to Amel, because Amel is the one that published the Super Maramu 2000 Owners Manual (page attached). 

Amps = Watts/Volts. 
Watts = Amps x Volts

So, either Amel is wrong with Watts or Amps, or both. 


On Wed, Oct 18, 2017 at 2:16 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:
 

What calculation did you do to convert 7000 Watts to 510 Amps?

P= V * A
510 Amps at 24 Volts = 12,000 Watts??

For what it is worth, the name plate on the motor on my older Super Maramu (they might not all be the same) is 6.3kW

To get a good number, for current draw you can't assume 24 Volts.  When you are drawing that much power, the voltage will drop, a lot.

For really high power draws like this, it is not unreasonable to assume as low as 18 Volts.

6,300 Watts/18 Volts = 350 Amps

If we do go with a 7000 watt rating, that's still "only" 388 amps.  A perfectly reasonable number to protect with a 500 Amp fuse.


Bill Kinney
SM160, Harmonie
Back Creek, Annapolis, MD




---In amelyachtowners@yahoogroups.com, wrote :

James,

From the Super Maramu 20 00 Owners Manual...it states 7,000 watts or 510 amps
Inline image 1
Best,



On Wed, Oct 18, 2017 at 11:53 AM, James Alton lokiyawl2@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Bill,


   Is it correct that the bow thruster on the Super Maramu is 500 Amps?  And that is at 24 volts?  The thruster on my Maramu has a 100 amp breaker installed by Amel ( it has never tripped so I assume the normal draw is something below 100 amps)  and the voltage is only 12 volts so if my math is right it is about 1.5 hp which is good up to about 15 knots or so.   500 Amps at 24 volts would be about 16 hp?  Can you tell me the size of the original Amel breaker that is installed on the Super Maramu?

   Thanks for all of your past help with my Amel.  And to update you on the bow thruster leakage.  After replacing the seals as instructed, the thruster did not leak a t all this season.    The thruster has also been 100% reliable thus far and is a tremendous asset IMO.

   I will con sider adding some inline fuses to my boat as well just in case of a major short. 

Best,

James Alton
SV Sueno,  Maramu #220






Craig & Katherine Briggs SN 68 Sangaris Tropic Isle Harbor, FL
 


Hi Bill,
Glad you were able to improve on the Captain's engineering!
Cheers, Craig

---In amelyachtowners@..., <yahoogroups@...> wrote :

Craig,

I agree with Alan's point and before we sold BeBe I had decided to place 6 of the Blue Sea 5191 MRBF Terminal Fuse Blocks with a removeable Blue Sea BS5185 (150A) amp fuse on each of the 6 positive battery pairs on the positive post  of the battery and connect the the positive lead for each pair to the newly installed terminal block fuse. My assumption was that the 500 amp bow thruster would not burn individual 150 amp fuses...I may be wrong on this. The fuses are available from 50 amps to 300 amps. Since the fuses are replaceable, I was going to buy extras.

Of course, I have not tested this, so I cannot say that it works and/or whether it is the best solution.


Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970

Bill & Judy Rouse <yahoogroups@...>
 

Craig,

I more than anyone saw the smile n your face as you wrote this posting....

BUT....

It is more like, "The Times They are a Changin'"😀

Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus

Amel School  http://www.amelschool.com
720 Winnie St
Galveston Island, TX 77550

+1(832) 380-4970



On Wed, Oct 18, 2017 at 5:02 PM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:
 


Hi Bill,
Glad you were able to improve on the Captain's engineering!
Cheers, Craig

---In amelyachtowners@yahoogroups.com, wrote :

Craig,

I agree with Alan's point and before we sold BeBe I had decided to place 6 of the Blue Sea 5191 MRBF Terminal Fuse Blocks with a removeable Blue Sea BS5185 (150A) amp fuse on each of the 6 positive battery pairs on the pos itive post  of the battery and connect the the positive lead for each pair to the newly installed terminal block fuse. My assumption was that the 500 amp bow thruster would not burn individual 150 amp fuses...I may be wrong on this. The fuses are available from 50 amps to 300 amps. Since the fuses are replaceable, I was going to buy extras.

Of course, I have not tested this, so I cannot say that it works and/or whether it is the best solution.

Inline image 1
Best,

CW Bill Rouse
Admiral, Texas Navy
Commander Emeritus


greatketch@...
 

James,

The SM does not have any factory installed protection for the bow thruster circuit.  On my boat the fuses on the battery terminals have a total rated load of 500 Amps, which is reasonable based on the ampacity of the wire used, and has never blown while in use.

And... since I am on the boat, rather than calculating, or looking up, or guessing...  I figured a bit of measurement is in order.  With fully charged batteries (and charger off) using the Magnetronic Amp meter to measure the current draw, and my Smartguage to simultaneously display voltage,  here is what I find:

The bow thruster draws 420 Amps at 24.1 volts.  That's where it stabilized after about 5 seconds.  That's with the boat tied tightly in a slip, so any movement of the hull would (slightly) reduce the load on the prop.

It figures...  almost exactly splitting the difference between what Amel has in the manual, and what the motor nameplate says.  If it matters, this motor was just professionally overhauled last year with new brushes, windings, etc.

Bill Kinney
SM160, Harmonie
Back Creek Annapolis, MD

---In amelyachtowners@..., <lokiyawl2@...> wrote :

Bill Kinney,

   Good point about the voltage drop. I measured mine as dropping from 13.5 (charger was on so this was not an accurate test) to about 11.75 after a 5 second burst. 

   Does the SM have a breaker for the bow thruster and if so can you tell me the amperage?   I guess that the 6.3KW rating doesn’t tell us much since we don’t know how loaded the motor is.  

   Also, can someone tell me about how much free play is normal for a bow thruster?  I can rock the prop on my thruster back and forth about 3/16” without any resistance as measured from the tips of the blades.  The output shaft does not seem to have any play in it’s bearing so I assume that what I am feeling is the gear lash plus any play in the shaft to motor splines.

James Alton
SV Sueno,  Maramu #220