Instruction manual

5. Adding and Replacing Optional Modules
151
Figure 5-12 Turning off the power
(1) Circuit breaker
(2) Power supply unit
Step 2
Set the circuit breaker of the power supply facility to OFF to turn off the power.
The circuit breaker of the power supply facility must be set to OFF.
Adding or replacing a DC power supply unit with the circuit breaker set
to ON could result in fire or electric shock.
Step 3
Disconnect the power cable from the power supply unit you are replacing. (For
details about how to disconnect the power cable, see 4.6 Connecting and
discon
necting the power cable.)