Victron energy Orion-Tr DC-DC Manuel page 12

4.5 Engine detection override
Applying >7V to the L-pin of the remote on/off circuit activates the
"engine detection override" function. The charger is on as long as
the "engine detection override" is active. With this function an
external control (e.g. ignition switch, CAN bus engine on detector)
can determine if charging is allowed.
The remote on/off function also needs to be activated so option a)
or b) in figure 3 must also be connected. See examples in figure 4
below.
Only an ignition switch
Figure 4: Engine Detection Override connection diagram
4.6 Cable and fuse recommendations
Figure 5: Cable and fuse recommendations
10
BMS