Teledyne 300M - Manual (Page 92)

Teledyne API Model 300M CO Analyzer Instruction Manual, 04033, Rev. A
9.5 Flow Readout Adjustment
The flow/pressure sensor board consists of 2 pressure sensors. The flow rate value is computed from
these two pressure sensors and displayed on the front panel TEST function including two pressure
readings. They are:
1. Inlet sample gas pressure - sensor S1
2. Vacuum pressure - sensor S2
The above pressures and flow are filtered to produce the front panel readings. Several minutes may
be required for a steady reading if observing the TEST functions.
1. Check pressure:
A. Remove the 1/4" fitting from the pump inlet.
B. Check the readings of VAC or PRES of the TEST functions.
C. Check if the pressure readings are close to the current absolute ambient pressure (typical
value at sea level is 29.9 in-Hg). Notice that it must be absolute pressure reading. Check if
both readings do not differ more than 2% from each other. Replace the pressure/flow
sensor board if defective.
2. Check Flow rate:
To check the sample flow, proceed as follows:
A. Scroll to select SAMP FL of the TEST functions.
B. Using calibrated independent flowmeter, verify the flow rate into the optical bench.
C. If the actual flow differs more than 10% on the displayed flow, proceed to flow
calibration.
3. Flow calibration:
A. Press SETUP-MORE-DIAG-ENTR and scroll to select FLOW CALIBRATION and press
ENTR.
B. Enter the actual flow value of independent flowmeter.
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