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68
8-1
Checking Operation
The hardware status of the PT can be checked with the Maintenance Menu.
Symptoms and corrective measures for errors that cannot be checked are
shown in the table below.
Symptom
Probable cause
Corrective measures, processing
POWER indicator
does not light.
Power is not being input, or power
supply is connected in inverse.
Provide a power supply with a rated voltage of 24 VDC.
Do not reverse polarity.
A fuse is blown.
Contact your OMRON representative.
Message indicates no
Host Interface.
No Host Interface Unit is mounted.
Mount a Host Interface Unit.
The System ROM is not compatible
with the Host Interface Unit.
Match the specifications of the System ROM and the
Host Interface Unit.
Screen does not
display.
System ROM is not installed, or
connections are faulty.
Check to be sure that the System ROM is installed, and
tighten the screws.
The memory installed does not
match the settings of SW2, or no
memory chip is installed.
Install a memory chip in socket and set SW2 correctly.
Contrast is not correct.
Adjust the contrast with the contrast control.
Cannot communicate
PT is not in Transmit Mode.
Select Transmit Mode from the System Menu.
with Support Tool.
There is a faulty connection with
the Support Tool.
Check connecting cables.
Cannot communicate
using Host Interface
U it (
i l
Switch settings are not correct.
Check PT settings under the Maintenance Mode and be
sure that settings match the host settings.
g
Unit (serial
communications)
Host Interface Unit connections are
faulty.
Check wiring of connecting cables.
Use shielded wire.
Check whether the cables are within the maximum
lengths.
For the NT600M-LK202, terminator
settings are not correct.
When using RS-422 communications, specify only the
last Terminal from the host as the terminator (turn on
termination resistance on the last Terminal only).
Cannot communicate
using Host Interface
Unit (parallel
communications)
The timing is off for
communications with the host
interface.
Check the timing of the DIP switch settings and the
host’s clock output.
Conduct a check using the “Communications Check” in
Maintenance Mode.
Lamp status is
retained when screens
are changed.
Lamps and touch switches are
overlapping.
Use touch switches as lamps just as they are. (Touch
switches have lamp functions.)
The buzzer sounds,
the RUN LED indicator
goes out, operation
suddenly stops, or the
display goes off and
does not return.
1) System ROM is not properly
installed.
2) Malfunction occurred due to
external noise.
1) Install the System ROM properly and lock it securely
in place.
2) Remove the communications cable from the source of
noise. Attach a noise filter to the power supply line.
Screen suddenly goes
blank.
Screen has changed to screen no.
0 at the host.
There is no error.
Corrupted Screen
Data
Screen data memory is bad.
The power was turned off or the
reset button was pressed during
transmission
1.) Replace the memory.
2.) Initialize the screen data memory and re-transfer the
data.
Checking Operation
Section 8-1