Siemens S5-135U/155U System Manual page 103

Other Faults
Other faults can be indicated by the green LEDs on the front plate going off.
Green LEDs go off
and the power
supply fails.
System Manual
C79000-G8576-C199-06
Central Controllers and Expansion Units Power Supply Units
LEDs Possible Cause
The Enable jumper is
out of place
l f il
Latching Off-switching
by overvoltage at
output
Internal fault in the
PSU
Base load too low
Action
Check the jumper.
Switch the supply voltage off and on
again. If this does not clear the fault,
there is an internal fault.
Send in the PSU for repair.
Increase the base load
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