Metek 920, Operator'S Manual With Essential Health And Safety Requirements

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3-10 | Model 920 Multi-Gas Analyzer
b. Adjust the Measuring Cell/Optical Bench Assembly so that the two
ribs of the Cell Extension seal fit firmly into the molded depres-
sions in the Oven and Electronics Enclosure walls.
Temporarily close the Electronics Enclosure door and tighten its
screws to secure the Optical Bench in place.
While closing the Electronics Enclosure door, verify that proper verti-
cal alignment of the Optical Bench is maintained.
If necessary, vertically align the Optical Bench by loosening the
Optical Bench support bracket from the backpan and moving the
Optical Bench up or down as required. After aligning the Optical
Bench, retighten the support bracket.
c. After the Electronics Enclosure door is closed and secured, ensure
no gap exists between the Heat Transfer Block and the Cell RTD.
The Measuring Cell must feel secure against the Heater Plate.
Gently push and pull on the Measuring Cell to verify it is not
loose.
If there is any movement, tighten the M4 x 25 screw again until the
Measuring Cell does not move, being careful not to over tighten it.
Do not use a ball driver. Over-tightening this screw will damage
the threads on the RTD.
d. Replace the Heat Transfer Block Plug in the Heat Transfer Block.
5. Connect the Sample and Vent Line tubes to their fittings on the
Measuring Cell.
6. Optional: If using the Optical Bench Purge, connect the purge line
(black tube) to the Purge Fitting on the Optical Bench.

NOTE