Noisy Or Unstable Readings At Zero; Noisy, Unstable, Or Non-Linear Span Readings; Slow Response To Changes In Concentration - Teledyne 401 Instruction Manual

Teledyne API Model 401 O

9.5.1 Noisy Or Unstable Readings At Zero

1. Check for leaks in the pneumatic system as described in Section 10.3.
2. Confirm that the Zero gas is free of Ozone.
3. Confirm that the Source Lamp is fully inserted and that the lamp hold-down thumb- screw is
tight.
4. Check for a dirty Absorption Cell and/or pneumatic lines. Clean as necessary as described in
Section 10.4.
5. Disconnect the exhaust line from the optical bench (the pneumatic line at the lamp end of the
bench) and plug the port in the bench. If readings remain noisy, the problem is in one of the
electronic sections of the instrument. If readings become quiet, the problem is in the
instrument's pneumatics.

9.5.2 Noisy, Unstable, Or Non-Linear Span Readings

1. Check for leaks in the pneumatic systems as described in Section 10.3.
2. Check for proper operation of the Main Switching Valve as described in Section 9.6.7.
3. Check for dirty absorption cell and/or pneumatic system components and clean or replace as
necessary as described in Section 10.4.
4. Check for proper adjustment of DAC and ADC electronics by performing the adjustment
procedure in Section 8.2.
5. Confirm the Sample Temperature, Sample Pressure, and Sample Flow readings are correct.
Check and adjust as required.
6. Verify sufficient flow from the O
flow needed is the sum of the M401 sample flow and the remote analyzers sample flow.

9.5.3 Slow Response To Changes In Concentration

1. Check for dirty pneumatic components and clean or replace as necessary as described in
Section 10.4.
2. Check for pneumatic leaks as described in Section 10.3.
3. Check for improper materials in the inlet manifold.
Photometric Calibrator Instruction Manual, 01124, Rev. J1
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generator in excess of the total flow needed. The total
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