Led "Ch1"/"Ch0" - Electrical - Siemens SIMATIC NET Operating Instructions Manual

2.5.3

LED "CH1"/"CH0" - electrical

LED color LED status
- Off
Yellow Lit
Red Flashing/lit
Depends on the cable length between the RS-485 interface and the problem and on the baud rate.
1
It can vary from one example to another.
Optical link module
Operating Instructions, 01/2020, C79000-G8976-C270-06
Meaning
Bus node is not connected, because:
Connected bus node is not turned on
•
Interruption of one or both wires of the RS-485 bus cable
• 1
Short-circuit or ground fault of the wires of the RS-485
• 1
bus cable
Signals are being received on the RS-485 bus cable.
Sporadic disturbances because of
Inadequate shielding of the RS-485 bus cable
•
Open bus cable, this means the RS-485 bus cable is only
•
connected to the module at one end
RS-485 segment is not terminated or only at one end
•
Pulling/plugging an RS-485 bus terminal or terminating
•
plug
Permanent disturbance due to:
Wires A and B of the RS-485 bus cable have been
•
swapped over
Short-circuit on the RS-485 bus cable
• 1
Transmission time exceeded due to a bus node in a bus
•
segment connected to channel 1 or 0
Permanent disturbance due to:
Module and another bus node connected over channel 1
•
or 0, transmit at the same time (e.g. because of duplicate
address assignment or slot time set too low or when can-
celing segmentation in the optical bus, see section "Bus
topology (Page 54)")
RS-485 driver of the module is faulty (e.g. following a
•
lightning strike)
Description of the device
2.5 LED display
Signaling contact
Does not signal
Does not signal
Signals
Does not signal
15