Omron SYSMAC FH Series User Manual page 414

2 Methods for Connecting and Communicating with External Devices
Problem
Data is sometimes output and
sometimes not.
Output is unstable.
*1. Commands to get status such as SCENE command allow you to confirm availability of communications be-
tween the Sensor Controller and external devices.
After starting up the Sensor Controller, send commands to get status from external devices to the Sensor
Controller. When the Sensor Controller returns OK responses to external devices, no problem in communi-
cations between them are confirmed.
Slow Operation
Problem
Response and data output is slow.
Communications Between the Sensor Controller and External Devi-
ces are not Correctly Done (EtherNet only)
Problem
The Sensor Controller cannot com-
municate with an external device
such as a PLC properly. (Only for
Ethernet)
2 - 352
Cause
Communications has not been es-
tablished just after the Sensor Con-
troller start-up. (It requires more
time to establish the communica-
tions.)
A cable is broken or there is a con-
nection problem.(RS-232C/422
communications only)
The measurement commands are
not being received. (Ethernet com-
munications only)
There is no terminating resistance.
(Ethernet communications only)
Cause
The baud rate is too low for the
amount of data to be transferred.
Cause
The communication settings such
as IP address have been changed
after the Device information storage
tool was performed. (The IP ad-
dresses for external devices on the
network may have overlapped the
IP addresses stored in the Sensor
Controller.)
FH/FHV Series Vision System User's manual for Communication Settings (Z342-E1)
Action
Check whether or not the communi-
cations are available between the
Sensor Controller and external de-
vices after the Sensor Controller
*1
turned on.
Then start communications and
measurement for ordinary opera-
tions.
Check the cable connections.
Check to confirm that an OK re-
sponse is being returned after
sending a measurement command.
Output stability may be improved
by adding terminating resistance in
RS-422 communications.
Action
Increase the baud rate for commu-
nications or use a different commu-
nications method.
Action
Check that the communication set-
tings such as IP address are cor-
rect. (Tool menu - System setting
- Communication - Ethernet) Per-
form the Device information storage
tool again. The communication set-
tings in the software will be copied
in the Sensor Controller.