Toshiba NV Series Hardware Manual page 6

Fix any the battery module to the DIN rail.
When using a battery module, install it
Instruction
near the controller unit.
Fix the battery module to the DIN rail so
that it may not come off due to vibration or
impact.
iv
6F8C1497
Protect the battery cable of the battery
module.
Instruction
If you use a battery module, connect the
battery cable to the battery connector on
the controller unit. Then, fix the battery
cable to the DIN rail so that it may not
come off by being caught.