Re: [Amel Yacht Owners] Santorin Bow Thruster Amperage Draw

James Alton


  You could compare the voltage drop at the battery terminals as compared to the motor terminals to get some idea of how much of the drop is in the cables.  It is possible that you may find that your batteries are a bit weak.  If you determine that a large part of this voltage drop is in the wiring, check all of the connections carefully.  Any connection with a high resistance will heat up with that much current and would feel warm or hot to the touch after running the thruster for several seconds.   If your batteries are holding their voltage well, and you are starting at 12.5 volts, you are dissipating 3.5 volts x 245 amps or 857 watts in resistance…a lot of power hence the heating.   This information is general in nature since my Amel experience is just beginning.

Best of luck,


Maramu #220 Sueno

On Jun 22, 2016, at 3:05 PM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@...> wrote:


Check this out:

I think you are in the ballpark. 

Bill Rouse
BeBe Amel 53 #387
Sent from my tablet
+1832-380-4970 USA Voice Mail

On Jun 21, 2016 11:39 PM, "sangaris@... [amelyachtowners]" <amelyachtowners@...> wrote:

Can any Santorin owners give me a bench mark for how many amps their bow thruster draws? 

Mine is showing 245 Amps after about 3 or 4 seconds of operation and stays constant with continued operation. 

This is with about 1500 rpm on the engine, generating about 35 amps before engaging the bow thruster (it is the original 70 amp Perkins alternator). The system voltage drops to 9 volts during this.  

The bow thruster does work perfectly through all this - I am just suspicious about the old wires/cables losing ampacity after some 24 years and one nearby lightning hit. On the other hand, this may be perfectly normal.  

I'd appreciate hearing if this is normal for the Santorin.


Craig Briggs, SN#68, Sangaris

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