KEYENCE GL-RHG Series - Manual (Page 126)

A-2 GL-RHG-M-NOA-E
App
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1
Troubleshooting
If the GL-RHG is not functioning normally, check the GL-RHG indicators first.
The GL-RHG is in an error condition under the following situations.
•
The center indicators blink in red.
• The 7-segment display indicates "".
If the GL-RHG does not demonstrate the above situations, the GL-RHG is not in an error condition.
Error condition
The GL-RHG performs self-diagnosis for approx. 2 seconds after the power is turned on and checks for
errors. Self-diagnosis is also performed periodically during normal operations.
If the self-diagnosis function detects an error, the GL-RHG goes to an error condition and the OSSD is
kept in the OFF state even if no interruption exists in the protective zone. The indicators operate in the fol-
lowing manner during an error condition.
7-segment display : Indication corresponding to the cause of the error
"Troubleshooting" (page A-2)
Center indicators : All indicators are blinking in red.
"Center Indicator" (page 5-4)
Error output : OFF
"Error output" (page 2-24)
To release the error condition, first remove the cause of the error, and then either activate the reset input
or turn the power off and on again.
 Self-diagnosis description
Transmitter Receiver
7-segment display
Function indicator
 Transmitter
• Error in the external power supply voltage
• Failure in the internal power supply circuit
• Failure in the light emitting element or light
receiving circuit
• CPU overdrive
• Memory error
• Cable open/short-circuit
 Receiver
• Error in the external power supply voltage
• Failure in the internal power supply circuit
• Failure in the light receiving element or detec-
tion circuit
• CPU overdrive
• Memory error
• Failure in the safety output circuit (OSSD)
• Cable open/short-circuit
• Program monitoring