question

steverj avatar image

Charging batteries from external charger

My system comprises two connected MultiPlus Compact invertors with back up charging by means of Honda generator. A small lizard chose the wrong time to enter one of the invertors (I was charging from generator) and was fried causing damage. The invertor works fine but will not allow me to charge externally. I have been advised that I need to send the invertor to a Victron repairer. I cannot do this as I need electricity! Is it possible to charge from generator through just the undamaged invertor- changing the wiring to suit. As a short term solution, can I attach external charger to the batteries (in-situ and connected to system) without causing damage to system. If I can, will battery charge meter still be accurate

battery charging
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2 Answers
steverj avatar image
steverj answered ·

Hi Paul, Thanks for taking the trouble to answer my query. I finally managed to get somebody to look at my problem. They tried to just charge from undamaged invertor but it would not work. They say this invertor is not working! They did not try to reconfigure the system or make any adjustments, just removed the cable from the generator feed to the damaged invertor. The invertor has has had a green flashing light for sometime - rather than a 'just on' light. Do you know what this means? I am not convinced the invertor is not working - is there any way I can be sure of this. Apart from the charging problem, the system seems to work ok and will produce exepected wattage in good sunshine.. They lent me a 20amp charger which gives me about 2% charge per hour - i have 3 x 200ah batteries. Obviously this is not ideal, I can try and buy say 40 amp charger, I assume my generator will be able to power this ok. I would be grateful for any advice you can give. Thanks Steve

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Paul B avatar image
Paul B answered ·

you can charge from another charger source this is fine, the battery SOC meter will then not be correct as you suspected,

otherwise if you run the gen then the undamaged inverter that still can charge will/should still charge the batteries.

or if you remove the damaged unit, then you could connect a MK3 to the 1 unit left and reset it to single inverter operation, then you will have power. you will need a laptop and the configuration software thats on the victron site, you should be conformable doing this as well, or get a tech who is

NOTE someone will then need to reconfigure it to parallel operation when the other unit is returned. and add back any assistants if they are removed etc etc


discuss the issue with the repair centre as they maybe able come out and install a loaner and take the old one away repair and return, or do the adjustments for you. NOT all repair centers offer this option.


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