Union Instruments CWD2005 SPC, Operating Instructions And Safety Notes

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OPERATING INSTRUCTIONS
CWD2005 SPC
chapter
— page:
4
—2
4.1 Main switch
Switches the power supply for the protective cabinets and the process gas analyser
in the protective cabinet.
Fig. 4.1: Main switch (example)
4.2 Compressed air purged and pressurised encapsulated housing GFK
Components that can cause ignition are installed in a housing that is purged with
compressed air. By the purging with air, the concentration of explosive gases
remains below the lower explosibility limit. The resulting overpressure prevents the
ingression of explosive gas mixed into the housing. Openings of the housing are
designed in such a way that transfer of a potential ignition hazard to the outside is
prevented.
4.3 Locks and door of the protective cabinet
The purged housing is closed with a door. The door is locked with 8 locks.
Operated by a square box key.
4.4 Flame arresters
Flame arresters prevent the propagation of a potential ignition hazard to other
system parts.
4.5 Cable / line glands
Cables and lines connected to the housing must ensure tightness in order to enable
overpressure by the compressed air purging.
4.6 Pressure switch, pressure too low
De-energises the system as soon as the pressure value falls below 0.8 inWC. Gas
inlets are closed.