Re: Shore power, small battery charger, genset, inverter.



It is impossible for me to know what has been changed since 433 was built. 

You should not switch power sources with any load. The SM2k originally had an automated relay switch that gave the generator preference and would switch the main AC distribution panel from shore power to generator power. Although it was not the right thing to do, the original battery chargers would be unaffected when this happened. You do not have either of the original chargers. I am not sure that you have the relay switch above, or if the relay switch is working correctly. Your SM did not have a "standard inverter." The comfort pack did not include an inverter. There was a small inverter installed with the TV option. Are you beginning to see that there is almost no way any of us can directly help you with the known information?

As Ryan pointed out, if the Main 220 breaker is opening immediately when the smaller charger is turned ON, the fault is most likely a ground fault. That ground fault is likely an issue with the internal electronics of that charger or the wiring to that charger. There is no way that I can foresee anyone being able to give you specific instructions to a solution. Additionally, I have no technician to recommend in Grand Cayman.

To further confuse the issue, you say, "The large charger is a (Mastervolt) Chargemaster 24/40-3" AND "The small charger is a Victron Skylla-TG 24 100" AND  If this is correct, it totally confuses me because you must have them reversed...the Victron is 100 amps and the Mastervolt is 40 amps. I am not sure which charger is working.

My best recommendation is to temporarily use only the charger that works and to find an experienced and certified marine electrician. 

When you SM was new and assuming it was sold with either the Comfort Pack or the original buyer invested in two chargers, they were: Dolphin 100 amp charger and a Dolphin 30 amp charger.  During most of the SM production, Amel did not have an inverter option but installed an inverter that the owner would provide. They installed it in the engine room and with separate circuits and receptacles for the inverter output. The AC panel and the Inverter circuit was totally separate. Amel also installed a small inverter with the TV option. That was located under the nav table. Many owners have since installed Victron Inverter Chargers rewiring the AC panel to give the Microwave and outlets direct "inverter only" power from the inverter charger. The Victron Skylla-TG 24 100 is a charger only, without the inverter capabilities.

I hope this helps you. If you would care to call me, maybe I can provide more help...number below...WhatsApp is fine.
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar

On Wed, Jul 22, 2020 at 5:23 PM Christopher Bromley <bromleyc@...> wrote:

Hello Bill,

              Thank you very much for responding so swiftly.

   I am with my boat in Grand Cayman, Cayman Islands. I had assumed the small charger and the 24V to 220V inverter were part of Pure Magic's comfort package, but other than the manufacturers' operating manuals - which I have read - I am not aware of installation documentation specific to my boat. Pure Magic had one previous owner and it may help if I contact him to see if he can fill in the information. If the problem with switching on the small charger and immediately  tripping  the main 220V breaker in the autopilot compartment (and this developed only after mistakenly starting the genset with the small charger still switched on - which the SM manual expressly advises against) does not sound familar to any one, then I should probably choose between looking behind the 220V switch panel or inside the small charger for a short ( after isolating the boat from mains power) or involving a specialist electrician. I am curious to know what type of damage risk the SM manual is cautioning against when it stresses the importance of not starting the genset when there are appliances still switched on at the 220 V switch panel.Is it damage to the genset or damage to the appliances?

  If there is any other approach you would recommend I'd be grateful for your advice..

          Thanks again for your help,

             Chris Bromley


On July 22, 2020 at 12:35 PM CW Bill Rouse <brouse@...> wrote:


I am not sure that anyone can help you here with confidence. Almost everything you listed is not original equipment. For instance a big question for me would be: Who added this equipment and is the installation documented?

Maybe we could suggest some help if you would state where you are. 


CW Bill Rouse 
Amel Owners Yacht School
+1 832-380-4970 | brouse@...
720 Winnie, Galveston Island, Texas 77550 
Yacht School Calendar:


On Wed, Jul 22, 2020, 10:40 AM Christopher Bromley < bromleyc@...> wrote:
My SM Pure Magic, hull no. 433, is presently connected to shorepower @ 220V, 60 Hz. During a recent inspection I was asked to operate the Onan genset, but overlooked switching off the small battery charger on the 220V switchboard before running the genset for a few minutes. Everything controlled from the 220V swichboard is working normally except the small battery charger which usually starts off at about 35A. Now the main 220V breaker inside the rotary autopilot compartment trips off immediately if I switch on the small circuit breaker. Resetting this trip and leaving  the small charger off restores 220v & everything else on the 220V switchboard works as before. There is no sign or smell of overheated circuitry, but I think there must be a short circuit somewhere. I'd really appreciate advice on how to troubleshoot this problem or could the small charger be fried beyond repair? The small charger is a Victron Skylla-TG 24 100, if I'm looking at the right unit.
 Another couple of electrical  questions while on the forum: the large charger I only use with the genset. Typically the charger starts at about 80 - 90 A, but soon - within a minute or two - falls to 20- 30 A and tails off at less than 10A even though the battery bank is short of a full charge, perhaps down at 70%. Is there a simple adjustment I can make to the large charger to keep up its output until closer to a full charge or does the charger need a specialist electrician's attention? The large charger has operated in this way for at least a couple of years. It is a Chargemaster 24/40-3.
 Lastly, I'd like to be sure of correctly identifying the 24V to 220V inverter, the one described in the owner's manual as being capable of running the microwave long enough from the 24 V battery bank to make a cup of coffee, after which it shuts down. Where is it in the boat and how do I get the microwave to run off it rather than from shorepower or the genset? 
   Thank you for your advice,
      Chris Bromley



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