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stvaughn avatar image
stvaughn asked

Multiplus Ii & batteries shut down on power transfer

Multiplus II-12/3000 2x120 in an RV application with 2-206AH SOK batteries, new install. When I disconnect the grid with no air conditioning on everything transfers normally and I can turn on AC‘s and microwave and everything works as it should. When I disconnect the grid while the AC is on the Multiplus shuts completely down and the batteries show no voltage. Not sure what I do to cause the system to restart but when inverter starts back up it shows “low battery” for a couple of seconds and then resumes normal operation. Batteries are not dead recharge back to float in just a few minutes

Everything is connected to AC output 1 and want to keep it that way if possible using solar and/or generator to power RV.

Help please, Steve

Multiplus-II
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2 Answers
Alexandra avatar image
Alexandra answered ·

@stvaughn

You batteries cannot take the sudden load, they are shutting down/tripping with the sudden current draw.

Not much can be done except add more battery maybe, or change the way you switch over power. What size DC cabling are you using?


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stvaughn avatar image stvaughn commented ·
4/0 battery cable, two 1/0 from inverter to Lynx power in buss.
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Alexandra avatar image Alexandra ♦ stvaughn commented ·
I would have gone bigger from the batteries to the lynx. Still does not help with the batteries say no and switching off though.

Solar if it is on at the time would be waking up the batteries then the system would recover on voltage.

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JohnC avatar image
JohnC answered ·

Hi @stvaughn

Take a look at this thread.. https://community.victronenergy.com/questions/2162/multiplus-boostfactor.html

You may find more too if you type Boost Factor in the Search box. I've no personal experience with this, but I'd be interested to know how you go if you try tweaking it.

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stvaughn avatar image stvaughn commented ·
Thanks, I’ll look into it.
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