Siemens ET 200SP HA Manual page 21

MT LED
Table 6-3
ACT LED
Table 6-4
PWR LED
Table 6-5
Interface Module IM 155-6 PN HA (6DL1155-6AU00-0PM0)
Manual, 05/2017, A5E39262148-AA
Maintenance display of the MT LED
MT LED Meaning
Maintenance is not required.
Off
Maintenance is required, meaning that at least one maintenance event has occurred.
On
Status display of the ACT LED
ACT LED Meaning (only relevant for IO device with redundant IM)
There is no active data exchange with the I/O modules via this IM.
Off
There is an active data exchange with the I/O modules via this IM.
The partner IM can apply the data exchange.
On
There is an active data exchange with the I/O modules via this IM.
The partner IM cannot apply the data exchange.
Flashes
Status display of the PWR LED
PWR LED Meaning
Missing supply voltage or insufficient supply voltage at the interface module.
Off
Supply voltage L+ available.
On
Displays and interrupts
6.1 Status and error displays
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