
Possible cause
1. No voltage on power cable;
2. Broken circuit or short circuit;
3. Beyond specified voltage;
4. Power cable exceeds the
specified length
1. There is reflection or cross-talk
from other transmitters
2. Walk speed set too long
3. Alarm output cable is shorted or
damaged
1. Beam is out of alignment; optical
axis does not overlap
2. There are objects between TX
and RX
3. Frequency is incorrect
4. The cover is dirty or capped by
snow, frost and ice
5. TX is faulty or OFF
1. Bad wiring and fluctuant power
voltage
2. Randomly blocked, like birds,
paper or leaves
3. The beams base is unstable
4. Out of alignment
1. Change beam path or change
TX/RX frequency channel
2. Ensure 2 beams all blocked
3. Change walk-speed setting
4. Check RX terminal and
output cable
1. Adjust optical axis
2. Check objects between TX and RX
3. Ensure the frequency of TX and RX
is the same
4. Clean cover or user heater
5. Check the voltage or wiring of TX
1. Check power, current and wiring
2. Change installation location
3. Strengthen installation base
4. Re-align
Symptom
Power on, but power
LED off
When beam is
blocked, the alarm
LED does not
indicate, nor does
the alarm relay switch
When beam is not
blocked, alarm LED
indicates activation
False alarm
Remedy
1. Check PSU, voltage, cables and
connectors
Auto Heating when it's ≤5℃ and stop heating when it's≥7℃