The DEYE BMS unit (HVB750V/100A-EU) for the high voltage battery cluster is supplied with voltage from the inverter as standard. This 5-meter two-wire DC cable is used to independently power the BMS unit from its own source and is an optional accessory . The cable is terminated on one side with a bayonet for connecting to the BMS and on the other side there are 2 insulated ends for connecting to your own 12V DC source.