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Commissioning
Commissioning the device in Modbus TCP
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8.8.5
Error Behavior (watchdog)
Behavior of outputs
In case of a failure of the Modbus communication, the outputs’ behavior is as follows, depend-
ing on the defined time for the Watchdog (register 0x1120):
Watchdog
Behavior of outputs
0 ms
All outputs maintain the actual value in case of an error
> 0 ms (default = 500
ms)
Outputs switch to 0 after the watchdog time has expired (setting in re-
gister 0x1120).
NOTE
Setting the outputs to predefined substitute values is not possible in Modbus TCP.
Eventually parameterized substitute values will not be used.
Behavior of the BUS LED
If the watchdog triggers, the BUS LED behaves as follows:
Watchdog
BUS LED
Tripped
Red
Behavior of the device in case of loss of Modbus communication
If Modbus is the active protocol and all Modbus connections are closed, the watchdog switches
all outputs to "0" after the watchdog time has expired, unless another protocol (PROFINET, Eth-
erNet/IP™) has been activated in the meantime.