Siemens SIMATIC S7-1500 Manual page 45

Meaning of the LED displays
The following tables explain the meaning of the status and error displays. Remedial
measures for diagnostic alarms can be found in the section Diagnostic alarms (Page 47).
Table 5- 1 Status and error displays RUN/ERROR/MAINT
LEDs
RUN ERROR
Off Off
Flashes Off
On Off
On Flashes
Flashes Flashes
Table 5- 2
PWR
Technology Module TM PTO 4 (6ES7553-1AA00-0AB0)
Manual, 12/2016, A5E38896703-AA
MAINT
No voltage or too low voltage on back-
plane bus
Off
Technology module starts up and
flashes until completion of the valid
Off
parameter assignment
The parameters of the technology
module have been assigned.
Off
Indicates module errors (an error is
present on at least one channel)
Off
Hardware or firmware defective
Flashes
PWR/ERROR status displays
LEDs
ERROR
Supply voltage too low or missing
Off Flashes
Supply voltage is present and OK
On Off
Indicates module errors (an error is
present on at least one channel)
On Flashes
Meaning
Meaning
Interrupts/diagnostic alarms
5.1 Status and error displays
To correct or avoid errors
Switch on the CPU/IM and/or the
•
system power supply modules.
Check whether the voltage connect-
•
ors are inserted.
Check whether too many modules
•
are inserted.
—
Evaluate the diagnostic alarms and
eliminate the error.
Replace the technology module.
To correct or avoid errors
Check the supply voltage.
•
Make sure that the front connect-
•
or is correctly inserted.
—
Evaluate the diagnostic alarms and
eliminate the error.
45