Cleaning And Inspection; Cleaning - Omron CQM1H-SCB41 Operation Manual

Cleaning and Inspection

Serial commu- Indicator
nications mode display
Serial communi- The COMM@
cations mode is indicators are
set to NT Link. flashing, but a
communica-
tions error
sometimes
occurs in the PT.
9-3

Cleaning and Inspection

9-3-1

Cleaning

Status I/O memory
information,
etc.
--- ---
Note The PT serial port must be set for a 1:N NT Link. The PT will not be able to
communicate with a Serial Communications Board if the PT is set for a 1:1 NT
Link.
Use the cleaning and inspection methods described here for daily mainte-
nance of the devices.
To keep the Serial Communications Board in optimum condition, regularly
clean the Serial Communications Board as follows:
• Wipe the surface of the Serial Communications Board daily with a soft,
dry cloth.
• If any dirt cannot be removed with a dry cloth, moisten the cloth with a
mild detergent diluted to 2%, and squeeze out any excess moisture
before wiping the Serial Communications Board.
• Do not adhere materials, such as gum, vinyl, or tape to the Serial Com-
munications Board for long periods of time. Doing so may cause stains on
the device. Remove any adhered materials when cleaning the Serial
Communications Board.
Note Never use benzene, paint thinner, or other volatile solvents, and do not use
chemically treated cloths.
Cause
Cables are incor- Review the wiring or switch
rectly connected. settings.
The RS-422A/485 Check whether the termi-
port setting (2-wire nating resistances of the
or 4-wire) is incor- host computer and the last
rect. node are set to ON, and the
terminating resistances of
Adapters such as the
other nodes are set to OFF.
NT-AL001-E are
incorrectly wired or
set.
A communications Review the wiring and
error frequently installation environment.
occurs due to noise,
Increase the number of
etc.
retries for the PT as
required.
The communica- Increase the communica-
tions monitoring time tions monitoring time for the
for the PT is insuffi- PT.
cient.
The load on the PC Lighten the load on the PC.
is too high.
Reduce the number of PTs
connected to each serial
port by using other ports for
some of the PTs.
Adjust the timeout and retry
settings in the PT.
Section 9-3
Remedy
133