Teledyne 300M instruction manual Flow Readout Adjustment

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.

9-6