WMA-5 Operation Manual V. 1.01
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Gas Ports
There are two gas ports (barb fittings) on the WMA-5. The gas inlet is located on the water trap and the
gas outlet is located on the bottom of the WMA-5 enclosure. Each port is designed for use with 1/8”
(.125) ID tubing. The sampling line should be fitted to the gas inlet port using 1/8” tubing. The gas outlet
should be left open to atmosphere to allow the sample air to exhaust without restriction.
Water Trap
The water trap (also referred to as a “Float Valve Housing”) is an essential filtration tool when gas is being
drawn to the CO
2
analyzer preventing the carry-over of water from getting into the system.
How the Water Trap Works
As liquid is collected in the bowl the level starts to rise, gas becomes trapped in the open-end of the float
and it too starts to rise. The entire float assembly then begins to move upwards and eventually closes the
valve and shuts of the flow to the analyzer. This loss of flow is then detected by the WMA-5 mass flow
controller ensuring flow is cut-off to the analyzer. An error message is also displayed in the Status Box.
Terminal Block
A terminal block is located inside the small rectangular enclosure below the main enclosure for simple
and convenient connection to external devices (i.e. power, RS232, power, microprocessors, etc.). To
access the terminal block, remove the two screws on either side of the enclosure to remove the cover.
We recommend that the terminal block cover is always fitted and secured in place during operation.