● The 5 system LEDs (PWR, NET, DC, S-ERR and I/O-Bus) show the operation state of the
module and display possible errors.
● The 29 process LEDs (UP, UP3, inputs, outputs, CH-ERR1 to CH-ERR3) show the process
supply voltage and the states of the inputs and outputs and display possible errors.
Table 153: States of the 5 system LEDs
LED Color Off On Flashing 1x flash 2x flash
PWR/RUN Green Error in the
internal
supply
voltage or
process
voltage
missing
Internal
supply
voltage OK
Module is
not config-
ured
-- --
Yellow -- -- -- -- --
NET Green Init Operational Pre-opera-
tional
Safe-opera-
tional
--
Red No error PDI
Watchdog
Timeout
Invalid Con-
figuration
Unsolicited
State
Change
Application
time out
DC *) Green Distributed
Clock not
active
Distributed
Clock active
-- -- --
Red -- -- -- -- --
S-ERR Red No error Internal
error
-- -- --
I/O-Bus Green No commu-
nication
interface
modules
connected
or commu-
nication
error
--- --- -- --
ETH1 Green No
EtherCAT
connection
Link OK
No data
transfer
Link OK
Data
transfer OK
-- --
Yellow -- -- -- -- --
ETH2 Green No
EtherCAT
connection
Link OK
No data
transfer
Link OK
Data
transfer OK
-- --
Yellow -- -- -- -- --
*) The state of this LED is only significant if the camswitch functionality is enabled
Communication interface modules (S500) > EtherCAT
2022/01/313ADR010278, 3, en_US722