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basti avatar image
basti asked

48V batteries and MPII, DCDC 48-12 - common negative? Yes/no, why?

Hello.


Can anybody give me (or point me to) a proper explanation if the negative from the batteries (48V) and the negative from the DC-DC-converter out (12V) can/should be made common?

Im my case the 48V batteries will feed the MPII, the BMS however requires 12VDC, and therefor I will also connect the CerboGX to the 12V sytem, because this will be buffered - in case BMS shuts off 48V Batteries, the BMS and Cerbo will remain running for a certain time to see what is going on in the system.

If memory serves right, then the Cerbo can only be connected to all other units, if they use a common negative (-)/ground?

So: Common ground yes/no? Why?


Thank you.

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1 Answer
Paul B avatar image
Paul B answered ·

I have cerbos on different power supplies and not on a common neg , I do not know of a reason as to why they would have to have a common Neg

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