Installing and connecting the device 
  3.3 Connecting the device 
SIMATIC IPC547D 
Operating Instructions, 06/2011, A5E03473780-01 
35 
Procedure - connecting redundant power supply 
 
 
1.  Turn off both on/off switches 
①. 
2.  Connect a power cable to the two sockets 
④. 
3.  Turn on the two on/off switches 
①. 
The LEDs on the power supply modules 
② 
light up green. 
Note: 
If only one of the power supply modules 
works, a warning signal sounds. You turn off 
the warning signal by pressing the 
③ button 
on the working power supply module. 
Securing the power plug of the redundant power supply 
To prevent unintentional removal of the power cable, you can secure the power plug as 
follows: 
 
 
1.  Remove the retaining screws 
①. 
2.  Screw on the latch for the power plug 
②.