Re: How to make the most of Victron Multi-Plus Inverter/Charger on SM#387

ngtnewington Newington

On Amelia I have a Trace 70A charger 2.5KW inverter that I bought to replace the old Dolphin 100A Charger that was defective when I bought the boat. I wanted an 100A charger but the Trace was on special offer and available at the time, from Budget Marine in Grenada.  With all my solar/wind that is absolutely fine on the charging side.

When it came to wiring in the inverter side I decided not to until I had spent some time on the boat. So it was initially only used as a charger. I found that I only wanted the inverter to use a toaster and a coffee machine, and vacuum cleaner and other minor appliances in the galley area.  I considered various wiring options, but they were all discarded . So what I have done is run a cable from the inverter 240v output to a  new single socket in the galley. Labelled 2.5KW inverter. 

I know this is a bit primitive, but I have found that it works fine. The advantage being that I have not messed with any of the Amel original AC installation. There is no risk of any generator/inverter/shore power contamination or confusion. I am still reliant on the original Amel installed automatic Shore Power/Generator switch. 

I am happy with this simplicity. In general when I run the washing machine; the desalinator is also running, as well as the hot water and chargers. I reckon that we would be pulling 30A, so 7.5 KW. A job for the 11KW Onan.

When installing new equipment on Amelia I am always mindful of the Amel way but more importantly the philosophy: 

Kind regards


S/Y Amelia AML 54-019

On 9 Dec 2019, at 15:47, Roque <ediroque@...> wrote:


I am sure what the Victron technician meant with shore power / generator was either one and not both, of course. The word 'simultaneously" was referring to AC and water heater use, in his example.


His point was only to help one chose between the 16A and the 50A transfer switch. 

Attika A54 #117
Paraty Brazil    

Em seg., 9 de dez. de 2019 às 12:22, Mark & Debbie Mueller <brass.ring@...> escreveu:
You stated that “For example, should a water heater and Air conditioning unit wish to be used simultaneously and in conjunction with shore power / on board generator the 50A unit would be chosen (50A - 11.5kW peak loads)”.  If I understand that you are connecting the shore power and generator simultaneously to the same circuit it is been my experience that catastrophic failures occur in the generator and likely some components between the generator and shore power unless the generator has some fairly sophisticated phase matching capabilities, I do not believe the equipment on our boats have that capability.  The generator must have the capability to match the peaks and valleys of the sine wave supplied by the shore power input.


Failures of this nature typically occur when a transfer switch fails connecting both shore power and generator.  Search message #46769 for a recent example of this on an Amel.

Mark Mueller
Brass Ring  A54

Join to automatically receive all group messages.