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3.3 Sensor replacement/servicing of detectors
Xgard
uses a modular design, which makes replacement of sensors, or
sinters extremely simple. Replacement sensors are supplied fitted to a
sensor PCB to allow simple plugin installation. An exploded view of
Xgard
is given in Diagram 3. The following procedure may be followed
when servicing a
Xgard
detector.
WARNING
This work should be carried out by Crowcon or an approved
service centre unless suitable training has been received.
1. Switch off and isolate power to the detector requiring attention.
2. Open the junction box of the detector by unscrewing the lid in an anti
clockwise direction (having loosened the retaining grubscrew first).
3. Unscrew the sensor retainer and remove the sensor and sensor PCB.
4. Fit the replacement sensor (having checked that the part number
matches that stated on the detector junction box label), taking care to
align the locating pins correctly with the slots in the junction box.
5. Refit the sensor retainer having first inspected the sinter to make sure
that it has not become contaminated. Contaminated items should be
replaced (see Spare Parts section for replacement part numbers), as
any blockages may result in slow sensor response to gas, and
reduced sensitivity.
6. Follow the Commissioning Procedure given in 3.1.
3. Operation
Xgard Type 6