Siemens Simatic M7-400 Reference Manual page 94

Power Supply Modules
Table 3-8 INTF, DC5V, DC24V LEDs, continued
LED
INTF DC5V DC24V
H D* D Short circuit or overload on 5 V and
24 V
H D* H/D ** Short circuit or overload on 5 V
H H D
If the standby switch is at the
position, illegal external supply on 5 V
If the standby switch is at the
position, short-circuit or overload on
24 V
D B H
Voltage restored after short circuit or
overload on 5 V if faults occur in
operation
Dynamic overload on 5 V
D H B
Voltage restored after short-circuit or
overload on 24 V if faults occur in
operation
Dynamic overload on 24 V
D B B Voltage restored after short circuit or
overload on 5 V and 24 V if faults occur
in operation
D B B Dynamic overload on 5 V and 24 V
D = LED is dark; L = LED lights up; F = LED flashing;
* If the power supply module does not start up again after a few seconds once the
overload has been removed, remove power to the module for 5 minutes and then
switch it on again. If the module stills does not start up, you must replace it. This
applies to 6ES7407-0KA01-0AA0, release 3 and for 6ES7407-0KR00-0AA0,
release ≤ 5.
** Depending on the short-circuit resistance
If either the 5 VDC or 24 VDC LEDs remains dark after switching on, the system
has not powered up.
If either of the 5 VDC or 24 VDC LEDs of the PS 407 10AR remains dark for longer
than 1 or 2 seconds after it is switched on, the power supply module will not start
up.
3-14
Cause of Fault
S7-400, M7-400 Programmable Controllers Module Specifications
Remedy
Check load on the power supply
module.
Possibly remove modules
Check load on the power supply
module. Possibly remove modules
Remove all modules.
Determine which module is faulty
Check load on the power supply
module.
Possibly remove modules
Press FMR momentary-contact
pushbutton:
Flashing light changes to constant light
Check load on the power supply
module.
Possibly remove modules
Press FMR momentary-contact
pushbutton:
Flashing light changes to constant light
Check load on the power supply
module.
Possibly remove modules
Press FMR momentary-contact
pushbutton:
Flashing light changes to constant light
Check load on the power supply
module.
Possibly remove modules
A5E00069467-07