7
1
1
1
1
1
1
1
TROUBLESHOOTING
No blue LED
The orange LED
is on.
There is no power.
The power supply voltage
is exceeding the acceptable
limits.
The sensor exceeds its
temperature limits.
Internal error
The polarity of the power
supply is inverted.
Check cable and connections.
Check the power supply voltage.
Verify the outside temperature where the sensor
is installed. Eventually protect the sensor from
sunlight using a cover.
Wait a few seconds.
If the LED remains ON, reset the power supply.
If the LED turns on again, replace the sensor.
Check the polarity of the power supply.
LED 2 is
permanently red.
LED 2
flashes red.
Faulty wiring
Faulty wiring
Verify connections (pins 6 and 7).
Verify connections (pins 6 and 7).
NOTES
Summary of Contents for U920
Page 2: ...2...
