Diagnostics
10.1 Status LEDs
PN/M-Bus LINK
42 Operating Instructions, 03/2018, A5E44260928-AA
On
On
On
Power-up test /
Serious error
• For approximately 1 second: LED test
during startup
• Longer than 1 second: HW error detected
during power-up test or other serious error
Off
Off
Off
System run-up
• System not completely booted yet but
power-up test is complete.
Flashes
Off
Off
Not connected to
S7 controller
• No "IO controller" connection established
or
• configuration not yet completed.
On
x
Off
Connected to S7
controller
• "IO controller" connection established and
configuration completed.
x
Flashes
Off
Error state
• "IO controller" connection established and
configuration completed, but an error oc-
curred:
– Diagnostic message to the S7 control-
ler is pending or
– Incorrect configuration by the S7 con-
troller
Flashes for at least 3 seconds.
Off
Off
Firmware update
• While the firmware is written to the flash
memory.
Flashes
Flashes
Off
LEDs are flash-
ing (triggered by
• 3-second intervals
• For identification of the device
1) The MAINT LED currently has no meaning.
x: LED state is irrelevant
When PN/M-Bus LINK starts up after the power supply is switched on, the process continues
as follows:
1. The three LEDs light up briefly for about 1 second and then go dark again.
2. None of the LEDs light up for about 4 seconds.
3. The RUN LED starts flashing.
4. Once the startup of PN/M-Bus link has been successfully completed and the connection
with the S7 controller has been established, the RUN LED lights up.