question

jswalwell avatar image
jswalwell asked

VE.BMS load disconnect... and reconnect?

Hi. I have an MPPT solar charger, a Victron Lion battery, a Ve.BMS and a pheonix inverter all hooked up. The charge diconnect wire goes to the MPPT to disconnect if over voltage, the load disconnect wire goes to the Phoenix inverter to disconnect if the cell/battery voltage is too low. My question is what happens when (in this system) the load is disconnected (because of under-voltage) then the solar panels/charger bring the battery back up past the load disconnect voltage? If the load disconnect re-connects (does it?), without hysteresis the load will draw the battery back down and disconnect again almost immediately. If the BMS will re-connect the load (?) is there a way to set at what voltage this happens?

BMS
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3 Answers
jswalwell avatar image
jswalwell answered ·

It looks like the MPPT has load disconnect and reconnect voltages, but the MPPT unit itself has no wire for this purpose. The BMS has the load disconnect wire/port. Does the MPPT instruct the BMS to disconnect/reconnect via the VE.direct port? If yes, then this solves my question.

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Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

What MPPT do you have?

The bigger ones have a remote port to connect to the 'charge disconnect' and for the smaller ones you need a special VE.direct cable.

https://www.victronenergy.com/accessories/ve-direct-non-inverting-remote-on-off-cable

This all should also be shown in the manuals of the devices.

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jswalwell avatar image
jswalwell answered ·

MPPT 100|30. Yes, I have the correct charge disconnect cable between the MPPT and the BMS. My question has to do with load disconnect and reconnect.

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