Victron Orion-Tr Isolated DC-DC Charger remote cables
 
In the Orion-Tr Isolated DC-DC Chargers the remote on/off circuit is referenced to the primary battery (e.g. starter battery). The Orion-Tr DC-DC Charger Isolated remote cable is intended for applications where the remote on/off signal is referenced to the secondary battery (e.g. lithium battery with BMS).