MSA 47K Series, Operation Manual

Page: 17 / 52

GB
MSA MAINTENANCE AND SERVICE
Series 47K Gas Detector [SIL 2]
17
5.2. Sensor Replacement
Caution
In a hazardous area, ensure all necessary precautions are taken
before opening the junction box. Replacement of the sensor or other
parts should only be carried out by suitably qualified personnel.
After checking if it is possible to carry out operation, according to the type of
danger in the area where the gas detector is installed, proceed as follows:
(1) Disconnect the power supply to the gas detector at the Control unit.
(2) Remove the sensor junction box cover.
(3) Note the wire colours and numbering of the terminal board and disconnect
the sensor wires.
(4) Unscrew the sensor from the junction box.
(5) Screw the new sensor into the junction box using the correct size of tool
across the hexagon flats.
(6) Connect the sensor wires to the terminal block and ensure they are
connected to the correct terminals.
Refer also to the wiring diagram in Section 10.
Close the sensor junction box cover and ensure that the gas detector is in
compliance with all relevant safety regulations and directives.