Inability To Zero - No Zero Key; Other Performance Problems; Temperature Problems - Teledyne 300E Instruction Manual

Model 300E Carbon Monoxide Analyzer
Instruction Manual
3. Make sure that the expected Span Gas Concentration entered into the
instrument during calibration is correct Span gas concentration too different
from expected span value. This can be viewed via the RNG Menu (see
Section 6.4).
4. Check to make sure that there is no ambient air or Zero Air leaking into Span
Gas line.
11.3.4. Inability to Zero – No ZERO Key
1. Confirm that there is a good source of zero air. Dilute a tank of span gas with
two the same amount of Zero Air from two different sources. If the CO
Concentration of the two measurements is different, there is a problem with
one of the sources of Zero Air.
2. Check for leaks in the pneumatic systems as described in Section 9.5.
3. The Internal zero air scrubber may need maintenance. This device is only
present if the analyzer has had Zero/Span Valve Options 51 or 53 installed
this.
4. Check to make sure that there is no ambient air leaking into Zero Air line.

11.4. Other Performance Problems

Dynamic problems (i.e. problems which only manifest themselves when the
analyzer is monitoring sample gas) can be the most difficult and time consuming to
isolate and resolve. The following section provides an itemized list of the most
common dynamic problems with recommended troubleshooting checks and
corrective actions.

11.4.1. Temperature Problems

Individual control loops are used to maintain the setpoint of the Absorption Bench,
Filter Wheel, and IR Photo-Detector temperatures. If any of these temperatures
are out of range or are poorly controlled, the M300E will perform poorly.
11.4.1.1. Box or Sample Temperature
Box Temperature
The box temperature sensor is mounted to the Motherboard and cannot be
disconnected to check its resistance. Rather check the BOX TEMP signal using the
SIGNAL I/O function under the DIAG Menu (see Section 11.1.3). This parameter
will vary with ambient temperature, but at ~30
the signal should be ~1450 mV.
P/N 04288 REV: A
TROUBLESHOOTING & REPAIR PROCEDURES
o
C (6-7° above room temperature)
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