GASMAX II Operation & Maintenance Manual, Revision 7.0
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3
INSTALLATION
SELECTING A LOCATION
Factors such as prevailing winds, gas density, potential leak sources, air movement machinery and similar
environmental variables are important when selecting a location for the GASMAX II gas monitor or gas
sensor. Even though the GASMAX II is designed for rugged service, sensors and electronics should be
protected from environmental damage due to water, snow, shock, vibration and dirt.
In addition, the sensor and / or display should be located such that regular maintenance and periodic
sensor replacement can be readily accomplished. While there are no industry standards for gas detector
placement, professional tools exist that can simulate leaks or spills and provide excellent guidance for
locating gas detectors throughout a facility.
MOUNTING THE GASMAX II
The GASMAX II standard enclosure is a cast aluminum explosion-proof
(NEMA 7) enclosure. Two channel GASMAX II units with dual local
sensor heads include
a “Y” adapter, shown at right.
Mounting ears are
located on both sides of the enclosure.
The GASMAX II or remote sensor should always be mounted with the
sensor head opening facing down. If necessary, a Splash Guard (p/n 10-
0205) should be attached if there is any chance that water or liquid spray
could enter the sensor opening from below. Be sure to leave sufficient
room (6
”
-
”
) below the sensor head to allow for air flow, easy access for
attachment of a Calibration Cup and / or removal of the sensor head
cover for sensor replacement.
MOUNTING A REMOTE SENSOR
GASMAX II remote sensors consist of a cast aluminum explosion-proof
junction box and stainless steel sensor head. The junction box contains a
PCB with an interface for the sensor head cable and wiring terminals for
the three-wire connection to the GASMAX monitor.
Fittings are all
¾” PT. The sensor head should
always be mounted
vertically as shown, and GDS Corp recommends side entry for all conduit
runs. GASMAX monitors support up to two remote sensors.
EXPLOSION PROOF INSTALLATION
GASMAX II monitors with standard explosion-proof sensor heads are
certified for use in Class 1 Division 1 hazardous areas. Installation in
these areas should follow required industry standard practices and all
appropriate electrical codes. Generally, these codes require rigid metal
conduit, poured seals and other installation elements necessary to
ensure safety.
Leave 8-
” open space
below gas detector for air
flow, sensor maintenance
and calibration
GASMAX II Remote Sensor
M E A S U R E M E N T N A M E
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