question

buddhafragt avatar image
buddhafragt asked

DVCC shared current sensor not working

I have 2 MPPTs connected to a Rasp Venus and DVCC switched on, a LiFepo4 with DIYBMS connected with CAN, it is a island setup with a Phoenix Inverter.

If the DIYBMS reduce the current for balancing, the current depends on the consumers switched on.

I adjust in DIYBMS for example to 1.5A balancing current and sometimes the current is 3A or sometimes -1,5A...

Someone know this problem?

MPPT ControllersVenus OSDVCC
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Alexandra avatar image Alexandra ♦ commented ·
@buddhafragt

I have seen the charge and discharge during balancing with other battery types as well.

I dont know that is can be called a problem. Some batteries discharge a bit to keep the balance under control.

Also dont forget if the system is trying to compensate for other consumers then it must produce or stop producing for those, there is bound to be a bit of give and take into the battery, since it is the most ready source of power and dump source.

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buddhafragt avatar image buddhafragt Alexandra ♦ commented ·

I can understand that there may be a delay here, but if I switch on a consumer and from the battery is now permanently taken 2A, although enough PV power is available, there is something compleately wrong.

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1 Answer
Mike Dorsett avatar image
Mike Dorsett answered ·

This is probably due to the minimum current setting possible for the Multiplus. Current step resolution is not very good, particularly at lower currents. MPPT trackers are much better at providing low controllable currents for balancing.

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buddhafragt avatar image buddhafragt commented ·
but I dont have a Multplus, I use 2 MPPTs....
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