Omron EJ1G User Manual page 171

Determining Errors from Indicators
HFU
Status
RUN Green, flashing
ERR Red, flashing
ALM Red, lit
150
Possible causes
There is an error in a channel
that is currently running.
There is an input error.
An error has occurred for which
the Operation During Error
parameter is set to MV at PV
Error or Stop control.
An error has occurred in commu-
nications with a connected TC4/
TC2.
One of the following alarms has
occurred: heater burnout alarm,
heater short alarm, or tempera-
ture alarm.
The power supply to the PLC
was interrupted after communi-
cations were established
between the PLC and EJ1G.
The communications cable was
broken after communications
were established between the
PLC and EJ1G.
An error has occurred in pro-
gramless communications.
Countermeasure
Read status to determine the channel that has
an error and then determine the cause from the
status of the ERR and ALM indicators.
Check the wiring for the input to be sure it is
wired correctly, not broken, and not shorted.
Also check the input type.
Read status to determine the nature of the error
and take appropriate measures.
Check the connection to the TC4/TC2 and take
appropriate measures.
Read the Error Channel A to D and the Channel
Alarm Status to determine the channel with the
alarm and the nature of the alarm, and take
appropriate measures.
Supply power to the PLC.
If the Operation Command Response Bits in the
Programless Upload Area set in PLC memory
are EEEE, write FFFF to the Operation Com-
mand Request Bits to restart communications.
Connect the cable.
If the Operation Command Response Bits in the
Programless Upload Area set in PLC memory
are EEEE, write FFFF to the Operation Com-
mand Request Bits to restart communications.
Check the following and correct any problems,
and then restart operation.
• Check the communications line lengths (trunk
and branch).
• Check the communications line for shorts,
breaks, or looseness.
• Check that terminating resistance is set only
on the ends on the trunk line.
• Check for excessive noise.
Section 7-2