7
TROUBLESHOOTING GUIDE
Symptom Possible Cause Remedy
Transmitter LED does not light. Improper voltage supplied. Check power supply and wiring.
Receiver power LED does not light. Improper voltage supplied. Check power supply and wiring.
Alarm LED does not light, even when
beams are blocked.
Infrared beam from transmitter is reflecting from another object and is being sent
into the receiver.
Remove reflecting object or change installation location and optical axis direction.
Two beams are not blocked at the same
time.
Check two beams to assure blocking at
same time.
Shorter blocking than the time set. Adjust blocking time to be longer.
Although Alarm LED lights when beams
are blocked, alarm doesn’t sound.
Broken or shorted alarm output wires. Check the wiring.
Blown fuse on the signal circuit. Repair as required.
Alarm LED on receiver does not turn off. Optical axis not aligned. Readjust the optical axis.
Blocking object between transmitter and
receiver.
Remove the blocking objects.
Dirty cover or reflecting mirror at transmitter and/or receiver.
Clean optics with soft cloth.
Bad wiring connection. Check wiring connection.
Change of supply voltage. Check for stabilized voltage.
Blocking objects blowing between transmitter and receiver.
Remove blocking objects or change
installation location.
Unstable sensor mounting. Stabilize mounting.
Marginal optical axis alignment. Readjust the optical axis.
Birds or other large flying objects interrupting the beams.
Readjust blocking time or relocate installation.
Intermittent Alarm