Siemens SIMATIC ET 200S Manual page 155

1SI 3964/ASCII, 1SI Modbus/USS serial interface modules
SF
Group
error (red)
TX RX
Status indicator
Figure 6-17 LEDs on the 1SI 3964/ASCII, 1SI Modbus/USS
ET 200S Distributed I/O System
EWA-4NEB780602402-09
LEDs
SF TX RX
On Hardware fault
Firmware error
Parameter assignment
error
Wire break or loose
cable between the mo-
dule and the communi-
cation partner
Communication error
On The module is sending
data via the interface.
On The module is receiving
data via the interface.
1
Only detected in the case of RS-422 interface connections when the
default for the receive line is set to R(A) 5V/R(B) 0V.
Commissioning and Diagnostics
Meaning What to do
Check the module
Check the parameteriza-
tion. Evaluate the diagno-
sis.
Check the wiring.
1
Check the communication
settings.
6-21