Maintenance / Repair
Repair
7
81
Building Technologies
007016_i_en_--
Fire Safety
2012-09-07
7.3
Repair
When false alarms or faults occur sporadically, it is important to know the cause.
Use the adjustment device and observe the signal strength over a longer period of
time. Compare the values with those on the label. The table below provides you
with an overview of possible faults and there remedy.
Perform an initialization after troubleshooting.
Fault
Possible cause
Remedy
Initialization has not been performed
correctly.
Repeat initialization.
Fine-tuning of the detector optics was
not performed correctly.
Repeat fine-tuning. Make sure that the signal is
set to the maximum value. At the end, perform
the initialization with the hood fitted.
The ray is temporarily interrupted by
obstacles (cranes, decoration, work
within the detection distance etc.).
Avoid interruptions to the infrared ray, or install
the detector in a different position.
The building may warp due to solar
radiation. The ray is deflected and no
longer reflected.
Mount the detector base on a solid, stable
surface.
The detector sporadically
triggers false alarms or faults
(depending on the selected
parameter set).
The detector or the detector unit has
been dislocated, e.g. due to an impact.
Ensure that the detector is fixed and the screws
are tightened.
Moisture condensation of the detector or
the reflector.
Install a detector heating unit DLH1191A.
Detection distance influenced by dust,
vapor or mist.
Select a less sensitive parameter set.
The detector sporadically
triggers false alarms.
The sun or other strong sources of light
directly shine on the detector.
Avoid direct contact with sunlight or use an
extraneous light filter DLF1191-AC.
The ray is reflected not only by the
reflector, but also by other objects (e.g.
ventilation ducts). This results in too high
a standardized signal value.
Cover the reflector and check the standardized
signal value on the adjustment device. This value
must be <5 %. If the standardized signal value is
greater than 5 %, remove the reflecting objects or
cover them with a non-reflecting material.
Radiant heaters cause air flickering and
thus have an influence on the detection
distance.
Install the detector and reflector in a different
position.
Strong soiling of the detector or reflector. Clean the detector and the reflector, then perform
initialization.
The detector sporadically
triggers faults.
Aging of the transmitter diode.
Initialize the detector again. If this does not
remedy the fault, replace the detector.
Fault on the detector line.
Check the line voltage.
The detector does not react
Detector defective.
Replace the detector.
Incorrect handling of the alarm test filter.
Place the alarm test filter directly on the
detector.
Rotate or turn the alarm test filter.
The alarm test filter does not attenuate
the signal enough.
Check the signal attenuation with the adjustment
device.
No alarm is triggered with the
alarm test filter.
Detector defective.
Replace the detector.
See also
Initializing the detector [➙ 75]
