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wytco0 asked

DVCC Maximum Charge Current setting - Is this expected behaviour?

My Multiplus II 5000VA 48v is temporarily connected to a 20 Amp MCB pending a CU upgrade. In order to make sure I don't overload the MCB I have limited the maximum charge Current in DVCC to 20 Amps.

My MPII is only connected to AC In 1 and is currently only being used to charge and discharge it attached batteries. Charging is enable by ESS.

The MP not handling or switching any high loads it is sensing the total load on the house via its attached CT clamp attached to the incoming tails, but if this is above 20 Amps limit set in DVCC it does not charge the batteries, we have a cheap rate at night and often pull more than 20 amps when ESS is set to charge and the batteries are not getting fully charged.

I am not 100% sure that this is what's happening as its difficult to see when the MP is actually charging, but if this is correct is it the expected behaviour? I had assumed that the MPII would use the 20 Amps to only limit what it was using rather than the house load?

I am running the MP II is On Mode but wondered if switching it to charge only might help, alternatively I could move the CT clamp elsewhere or revert it to the jumpered local measurement that it was delivered with.

Multiplus-IIESSLithium BatteryDVCC
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2 Answers
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ejrossouw answered ·

The setting in DVCC is DC A, which is not the same as AC input A. 16A AC is roughly 70A DC depending on your DC charge voltage and AC line voltage. You can remove the limit and maybe consider setting it to 50 or 60A. Personally I will charge at 75-80%. Make sure you monitor the connections and cables to ensure it can handle the current especially with prolonged high current charging.

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wytco0 avatar image wytco0 commented ·
Thanks you I really should have realized that it was DC related earlier. By 75-80% are you are talking about 75-80% C?
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ejrossouw avatar image ejrossouw wytco0 commented ·
The charging current should be set up as per your battery chemistry and manufacturer's recommendations. A MP-II 5kVA charger is rated 70A max and I will typically configure systems to charge at 50 - 60A as long as it is in line with the battery specifications.
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wytco0 avatar image wytco0 ejrossouw commented ·
Yes understood thanks my 304Ah Eve cells are recommended at .5C charging but I will reconfigure mine to 50 Amps DC, I have a 6 hour cheap rate window for charging and don't need to push them too hard.
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kevgermany answered ·

Outside of DVCC, in VRM dashboard, you can set the AC input current limit. Use the switch icon, top right. If the icon isn't there, you need to enable override by remote using VE config and an mk3 to usb adapter.

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wytco0 avatar image wytco0 commented ·

Thanks for that I checked mine and I had already set it to 16 Amps, its doesn't offer 20 Amps so I will stay under the 20A MCB limit for now although I expect the MCB would not trip at 25A.

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