Troubleshooting By Symptom; When The I/O Module With Diagnostic Functions Does Not Start Up; When The On/Off State Of An External Input Cannot Be Read - Mitsubishi Electric MELSEC iQ-RX40NC6B Application User's Manual

3.3

Troubleshooting by Symptom

When the I/O module with diagnostic functions does not start up

Check item
Check whether five seconds have elapsed after power-off of the power supply
module.

When the ON/OFF state of an external input cannot be read

Check item
Check whether a disconnection is detected.
Check whether the I/O status indicator LED (X0 to XF) of the input module
with diagnostic functions turns on when the external input device is on.
Check whether the input delay function has been properly used.
Check whether the system parameter "Inter-module Synchronous Setting" is
correct.
Check whether the module has been selected as the synchronization target
module.
Check whether the external power supply is supplied.
If the ON/OFF state of the external input still cannot be read even after the actions described above are taken,
the possible cause is a failure of the input module with diagnostic functions. Please consult your local
Mitsubishi representative.
3 TROUBLESHOOTING
64
3.3 Troubleshooting by Symptom
Action
When applying the input power source to the power supply module again, do
so five seconds or more after the shut-off of the power.
Action
If the RUN LED and ALM LED are on, a disconnection in the input wiring may
have been detected. Check 'Latest alarm code' (Un\G2564) to check whether
a disconnection has been detected.
If a disconnection has been detected, take the action for the input
disconnection detection (alarm code: 88H) described in the following.
Page 70 List of Alarm Codes
When the LED does not turn on, the input wiring has problems. Check
whether the input wiring has been disconnected or short-circuited and the
voltage of the input signal is proper, and review the wiring.
For the rated input voltage, refer to the performance specifications described
in the following.
 MELSEC iQ-R I/O Module (With Diagnostic Functions) User's Manual
(Startup)
When the input delay function is enabled, input signals will turn on or off
according to the set input delay type when the delay time has elapsed after
the external devices turn on or off. Disable the input delay function, or review
the delay time.
For details on the input delay function, refer to the following.
Page 24 Input delay function
• If "Use Inter-module Synchronous Function in System" is set to "Not Use",
change the setting to "Use".
• If an expected value has not been set in "Fixed Scan Interval Setting of
Inter-module Synchronization", set a correct cycle.
If the input module with diagnostic functions has not been selected as the
synchronization target module, select it as the target module.
Check that the voltage of the external power supply is within the rated range.
For the external power supply, refer to the performance specifications
described in the following.
 MELSEC iQ-R I/O Module (With Diagnostic Functions) User's Manual
(Startup)