13 TROUBLESHOOTING
13.3 Troubleshooting by Symptom
195
13
When the ALM LED is flashing
When an I/O LED does not change
When a module parameter error is displayed in the "Module
Diagnostics" window
When the ON/OFF state of an external input cannot be read
Check the following items in order of No.
Check item
Action
Check whether the system was restarted after the activation of the safety
module.
When the safety module is enabled, restart the system.
Check item
Action
Check whether "Display I/O status and error switching (1 second interval)" or
"Always display I/O error" is set in "LED display settings during an error" of the
input module with diagnostic functions.
Check whether "Display I/O status and error switching (1 second interval)" or
"Always display I/O error" is set in "LED display settings during an error" of the
output module with diagnostic functions.
Check the current setting of "LED display settings during an error".
Check item
Action
Check whether the module configuration is correct.
Check that the module configuration is the same as the one set with the
engineering tool.
Check whether a module incompatible with the SIL2 mode is not used.
Check that modules whose firmware version are compatible with the SIL2
mode are used. Incompatible modules do not operate normally in SIL2 mode.
For details, refer to the following.
Page 141 Firmware Version for SIL2 Mode
No.
Check item
Action
1
Check whether the S MODE LED is on.
If the S MODE LED is not on, take action by referring to the following.
Page 194 When the S MODE LED is flashing or off
2
When the external input signal is on, check whether the
corresponding input LED is on.
If the LED is not on, check again the wiring between the external input device
and the module's external input terminal. Also check that the voltage of the
module's external power supply is within the rated input voltage range.
3
Check whether the read safety device is correct.
If a safety device different from the safety device assigned by the refresh
device setting is referred to, the safety device cannot be read correctly.
Check the refresh device setting, and make necessary corrections to make
the program content consistent. (
MELSEC iQ-R CPU Module User's
Manual (Application))
4
Check whether "Wiring input selection" is set to "Not used".
When "Not used" is set for "Wiring input selection", the relevant safety input is
always OFF. Change the "Wiring input selection" setting according to the
actual wiring.
5
Check whether two signals of double input wiring match.
When "Wiring input selection" is set to "Redundant (NC/NC)", as long as the
levels of two paired input signals do not match, a state of the safety input level
being different from the actual input signal level continues. Check whether the
external input device is faulty or whether the wiring between the device and
the external input terminal is correct.
Summary of Contents for MELSEC iQ-RX40NC6B
Page 1: ...MELSEC iQ R I O Module With Diagnostic Functions User s Manual Application RX40NC6B RY40PT5B ...
Page 2: ......
Page 125: ...4 OVERVIEW 123 4 MEMO ...
Page 191: ...12 MAINTENANCE AND INSPECTION 189 12 MEMO ...
Page 227: ......