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Tetra gas test accessory kit
The Gas Test Accessory is a gas testing kit designed to enable gas testing of the
Tetra multigas detector using a specially formulated, high stability long life quad
gas mix. It can be used with Tetra units having sensors for Flammable, Oxygen,
Carbon Monoxide and Hydrogen Sulphide gases, and all Tetra units with these
sensors can be gas tested using the kit.
6.1 Gas testing
Gas testing checks the sensor is responding within set limits to an applied gas
of known composition. This can be performed as often as desired, but would
usually be carried out each time the Tetra is issued for use. The Tetra itself will
determine Pass/Fail status for the gas test.
In order to perform successful gas tests ensure:
• The quad gas mixture used has the correct gas concentration, and that
it is within the validity date specified by the supplier.
• The gas flow path is leak tight. It is important to check that the flow
plate is properly fitted to the Tetra, and the outlet tubing is not restrict-
ed in any way, nor additional tubing length used.
The Gas Test Accessory Kit is supplied in a convenient carry case and comprises;
a gas cylinder containing the quad gas mix, a 'Trigger' regulator with intercon-
nect tubing, a magnet - used to activate Test mode, an aspirator plate to attach
to the Tetra and a vent line. The Trigger regulator can be operated in two ways:
(1) squeeze and hold - allows gas flow as long as the lever is held in, or (2) by
lifting the lever - the flow is locked on. There are two versions of the kit; one
for pumped Tetra units and one for non-pumped Tetra units supplied with an
aspirator plate. Pumped Tetra units require the use of the plate with the integral
bellows assembly.
6.2 How to perform a gas test
1. Ensure your Tetra unit is switched on and in normal operation.
2. Clip the flow plate onto the front of the unit and attach the hose from
the Trigger regulator.
Attach the outlet hose to ‘vent gas away’ - do not extend this hose
and do not restrict or allow kinks.
3. Swipe the magnet past the display adjacent to the LED lens. Your Tetra
unit will activate the Gas Test and show ‘GAS TEST’ on the display.
4. Tetra will display a progress bar at the bottom, the names of the gas
Gas testing Tetra