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mrdias avatar image
mrdias asked

Should i use a Battery protect with Smart MPPT and LifePO?

Hi, I see some builds over the internet that have a battery protect between the MPPT and Battery connected to a BMS (all victron). Is this really required? Doesnt the MPPT stop the charging if voltage is set right on the MPPT settings?

I have set the MPPT battery to LifePo but i havent test if it works, i am afraid to go over the voltage.


Thanks

MPPT ControllersLithium Battery
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1 Answer
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

To prevent overcharging you should use a "VE.Direct non inverting remote on-off cable"(ASS030550320) and connect it to the "charge disconnet" terminal of the BMS and the VE.direct terminal of the MPPT.


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mrdias avatar image mrdias commented ·

Thank you for your reply, so the MPPT on its own will overcharge the battery even tho its set to lithium?

I am already using the VE.direct cable to the Color Control and i am already using the charge disconnect for the starter battery relay.

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Matthias Lange - DE avatar image Matthias Lange - DE ♦ mrdias commented ·

Normally the MPPT should stop charging by itself at 14.2V.

But if there is some kind of failure in a cell and the BMS says "stop charging", the MTTP have to be turned off.

If the VE.direct terminal is already in use you maybe should use a Cyrix-li-charge(or Battery Protect) to cut-off the MPPT or you connect the MPPT to the starter battery.

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mrdias avatar image mrdias Matthias Lange - DE ♦ commented ·

If the BMS is giving 12v on the charge disconnect port untill it cuts it incase something is wrong, cant we connect more than 1 batery protect in paralel in that charge disconnect port?

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