Panasonic HL-G1**-A-C5 User Manual page 134

Type Problem
RS-485
communication
control cannot be
done.
COM
Normal
communication
over RS-422/485
is impossible.
RS-485
communication
control cannot be
done.
COM
Normal
communication
over RS-422/485
is impossible
The settings are
SET
wrong.
Ramco National 800-280-6933 | nsales@ramcoi.com
Cause
The wiring is incorrect.
The RS-422/485 connecting
cable is disconnected.
The wrong connection mode
and baud rate are selected.
The communications
settings for the external
equipment are wrong.
The sensor number
settings are wrong.
The selection of the
terminating sensor is
wrong.
The communication quality
is degraded as a result of the
wiring condition.
Check that the correct
Sending delay time is set.
An incorrect data format
or command is
transmitted.
Several commands are sent
continuously without
waiting receiving responses
from the controller.
The settings were not
saved while RS-422/485
communication was
used.
Corrective action
RS-422 and RS-485 are different in
wiring. Connect the wires correctly.
Use a twisted-pair cable to ensure
stable communication.
Check the connection between
RS-422/485 cable and connector.
Connect the connection mode
and baud rate correctly.
Check the settings for the external
equipment (e.g., the
communications board) and be
sure to set the correct RS-422/485
communications specifications.
If a number of sensors are connected
over RS-485, be sure to set a unique
sensor number for each sensor.
Select the terminating resistor
(R3) only for the terminating
sensor head only. Be sure to turn
OFF the terminating resistor of
the rest of the sensor heads.
The communication condition may be
improved by lowering the baud rate.
The communication condition may be
improved by selecting the R1 or R2
terminating resistor.
In the case of connecting a number of
units over RS-485, reception errors in
the host device can be avoided by
delaying the sensor's response time.
Refer to the error codes and
send the data with the correct
format and command.
Send the next command after the
controller transmits the response
to the previous command.
The execution of the Save
command is required after making
setting changes with the
communications command (by using
the Setting and Monitoring Software
HL-G1SMI or the dedicated console.
The set value will be discarded with
the power turned OFF if the set value
is not saved.
www.panasonicsensors.com
Ref.
page
4-2
4-3
4-4
4-2
3-36
4-2
3-35
4-4
3-34
3-34
3-36
3-38
4-8
4-16
4-6
3-43