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r-d asked

Pylontech BMS - max current limits (charge/discharge)

Hi - my setup is as follow:

- 1x Cerbo GX

- 1x MultiPlus-II 48/5000/70-48

- 2x Pylontech US2000C (connected as recommended)

- 1x 60A DC fuse between Multi and batteries

- configured as recommended (https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom)


I understand that one US2000C can provide 25A continuous charge and discharge and 100A peak for 1 minute.

DCL is set to 50A and CCL is set as well to 50A - I assume automatically by Pylontech BMS.

I noticed, some peeks going up to 40A for more than a minute (VRM portal).

Question 1 - is this now based on the fact that DCL and CCL is set to 50A?

Question 2 - If DCL and CCL is set to 50A, will this being real max or can it still happen that there will be a peak of upto 100A? Please keep in mind, my fuse is 60A and such a peek would kill my fuse ;-)

Thank you in advance

Multiplus-IIcerbo gxBMSPylontech
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2 Answers
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nickdb answered ·

You have an inverter that is capable of sustaining 100A, more at peaks, so your pack is way undersized, the docs want 4 of those batteries for a 5kVA inverter. The inverter will try to honour the BMS provided limits, but there are various scenarios where that isn't possible (grid failure, transients etc) and it will pull what it needs for as long as it needs until the BMS blocks the battery discharging.

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r-d answered ·

Thank you for comming back to me.

Does that means, I should change my current fuse from 60A to 100A?

Or is the current (victron) fuse able to cover these kind of peaks/situations?

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nickdb avatar image nickdb ♦♦ commented ·
Fusing is to protect the cabling, so should be rated accordingly, as to the specs victron use, that I am not familiar with.
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