Fault Messages And Trouble Shooting - Raychem EMDR-10 Handbuch

4. Fault Messages and Trouble Shooting

The following faults are being detected by the control unit:
Fault
Break or short circuit of the temperature sensor
Break of the moisture sensor
Short circuit of the moisture sensor
Power failure
Notice:
- A short circuit at the moisture sensor leads to the triggering of the fuse.
- By that a short circuit is being detected as well because it leads to a break of the sensor cir-
cuit.
In case of a fault at the moisture sensor the moisture measuring circuit will be switched off. The
LED "moisture" will continue to flash. After repair of the moisture sensor the fault signal has to
be cleared by activating the TEST mode (turn the potentiometer for the lower temperature limit
to the left stop and shortly after that back again to the requested lower temperature limit). When
the air temperature falls below the value adjusted at the control unit, then the moisture sensor is
activated and tested again after approx. 10 minutes.
Trouble shooting:
Symptoms
Heating cable not heating Moisture sensor not positioned
(snow is not melting)
Temperature below set
point, but heating cable
fails to operate
Snow present,
but heating cable fails
to operate
Snow begins to clear,
but the heating cable
turns off too soon
10
Probable causes
correctly (e.g. not flat in the gutter) in the "Assembly of the Moisture
Temperature sensor located in
direct sunlight
Moisture not detected
Less than 10 minutes have elapsed The moisture sensor is not checked
since the temperature fell below the for the presence of moisture until
setpoint
below the setpoint
Moisture dial set too high
Poor positioning of the moisture
sensor
Poor positioning of the moisture
sensor
Moisture dial set too low
Temperature has fallen below
minimum temperature setpoint
Reaction
LED "temperature" flashes,
alarm relay and load relay switch off
LED "humidity" flashes,
alarm relay and load relay switch off
Additionally, under short circuit conditions,
Moisture sensor fuse will rupture.
Alarm relay and load relay switch off
Correction
Re-position following the instructions
Sensor" section of this manual
Re-position following the
instructions in the "Assembly of
the Temperature Sensor" section of
this manual
This is normal operation: low temper-
ature AND moisture must be detected
before the heating cable is energized
10 minutes after the temperature falls
Set the moisture dial to a lower
value
Re-position following the instructions
in the "Assembly of the Moisture
Sensor" section of this manual
Re-position following the the instruc-
tions in the "Assembly of the
Moisture Sensor" section of this
manual
Set the moisture dial to a higher value
This is normal operation