SST GT814, Design Manual

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814-4 September, 2015
MODEL GT814 NOVA-Sensor ELITE™ Toxic Gas Detector
“ONE HOUR” INSTALLATION INSTRUCTIONS
The Model GT812 Toxic Gas Detector is shipped fully as-
sembled and pre-calibrated to the full scale range of toxic gas
that you have specified with your order. It can be installed and
be fully operational in less than one hour. Various protection
accessories required for use in hostile environments are already
installed on some detectors.
1. Mount the Detector Electronics Enclosure
Secure the electronics to a wall or bracket, using bolts through
the two mounting holes. Locate the unit at a convenient place
where the viewing screen and LED’s can be easily seen through
the window on the front of the enclosure. Most NOVA-Sen-
sor ELITE detectors are shipped with the sensor preinstalled
onto the electronics housing as shown here.
2. Open Detector Housing and remove Electronics Module
Loosen the hex head set screw on detector cover
(a 7/64 inch hex wrench is required) and turn cover
counter clockwise to remove.
Use a small screwdriver inserted under the edge
of the electronics module in the 3 locations marked
“pry up” to loosen the module from the connector
and remove it from the enclosure.
3. Mount Sensor Head at a Remote Location (optional)
The toxic gas sensor head that is installed on the bottom port of the enclosure may be re-
moved and installed at a remote location if desired.
!
If the gas sensor head is not to be removed from the Electronics Enclosure, skip this section
and go to step number 5 below.
To remove the sensor head, disconnect the Red and Black sensor wires from the terminal
block inside the enclosure. Then unscrew the sensor from the electronics enclosure. Install the
sensor in a suitable junction box for the remote location. The sensor thread size is ¾ inch NPT.
Mount the remote sensor in the location chosen for best and
fastest response to leaking gas, as explained on the previous
page. Lighter than air gases, sensor mounts on or near ceiling
of enclosure. Heavier than air gases, sensor mounts about 1
foot (30 cm) above floor or ground. Preferred orientation is
with the porous metal sensing face pointed downward. Never
point the sensor face upward to insure that no moisture or dust
collects on the sensor face to reduce sensitivity and damage
the sensor.
This picture shows the sensor mounted with wiring junction
box and optional remote calibration adapter installed. The
adapter tubing is used to apply test gas to the sensor during
testing and calibration.