Gen2/Charging Control Unit
The Charging Control Unit (CCU) on Meanwell-charger-equipped models (all 2013 and the 2014FX) collects battery temperature sensor data, battery voltage, and charger DC voltage to decide on whether to open or close the contactor. It also manages the Meanwell onboard charger which has no CANBus connection or programmability, so when the programmable Calex charger was introduced, the CCU's functions were moved to direct BMS/MBB management.
- more from Burton's post here: Re: 2013 S 11.4 quick charger build
The contactor protects the battery against faults. It is analogous to a circuit breaker. The CCU directs it.
2012-2013 models exhibited behavior where the BMS in certain situations yielded a "contactor welded shut" condition that require dealer servicing. Later model years fail more safely (open).
2014+ models do not have a CCU, and the BMS directly controls the contactor and onboard charger.
- Under the seat in front of the MBB with the connections mounted on top.
- The CCU terminals are not designed for high amperage currents. Presumably, anything above the 2013's intended 30A charging limit could damage the CCU or trigger the contactor opening.
|Warning Warning:||This is always energized. Any exposure of this at any time will risk direct contact with battery terminals that could result in injury or equipment damage.
If you are in a remote location, and have trouble with a contactor unit not closing without any indication of a particular condition that interlocks it in the BMS, a little mild mechanical agitation (while the vehicle is keyed off) against the top surface with a rubber mallet might loosen it.