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mark-leckenby avatar image
mark-leckenby asked

Multiplus II 5KW Inverter (Paralleled) randomly keeps turning off for no apparant reason

I have a parallel configuration of 2 x Multiplus II 5KW inverters running in ESS mode with 12kWh lithium battery and DC coupled solar. The inverter "Switch" (shown below in the remote console below) randomly turns off every now and then for no apparant reason. I have attached below the most recent incident of this occuring at 09:00 on 9th AUG. As you can see the load is ony 250watts and there are no alarm notifications on 9th AUG to indicate why this has occcured. Help is appreciated. I am able to provide a log in access to this portal for an expert that can potentially help solve the mystery...

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Multiplus-IImultiplus in paralleless settings
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2 comments
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Paul B avatar image Paul B commented ·
what BMS and batteries are you using, and how is the BMS connected to the system



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nesswill avatar image nesswill commented ·

Above you are showing Volts & amps? not watts.

And if you are @ 230v @ 50a that 11500w.

Sorry if i have misunderstood.

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3 Answers
rata1 avatar image
rata1 answered ·

Check the tightness of the remote on/off screws. One of mine was loose from the factory and randomly shut down.

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Since I screwed it in, no issues.

https://community.victronenergy.com/questions/182506/random-loss-of-ac-out1-why.html?childToView=218289#comment-218289



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Paul B avatar image
Paul B answered ·

Another issue could be

Here you are showiing a output of around 50 amps at 240 volts thats 12kw output on a 10kw system if temp is at oir under 25Deg C - so it maybe shutting down on overload - or batterys are two small for the job and you are getting a voltage drop.



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Another


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nickdb avatar image
nickdb answered ·

The GX should record an error condition under notifications, this should be reported on vrm as well under alarms.

Is anything recorded there?

You may also be exceeding the battery discharge limit, given it is a fairly small capacity to inverter ratio, typically that doesn’t bode well for a sufficiently high DCL.

Does the BMS report anything?

Have you used a clamp meter to confirm if the load is evenly distributed across inverters?

From the charts you do seem to be exceeding the system spec.

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