Teledyne API Model 200AH NO
X
Analyzer Instruction Manual, 06492, Rev. G2
9-53
9.3.7. Flow/Pressure Sensor
The flow/pressure sensor board consists of 2 pressure sensors and a flow sensor. See Figure 9-8
for a diagram of this board. From these three sensors four values are computed and displayed on
the front panel TEST functions. They are:
1. Ozone Flow - measured directly - S3, R3
2. Reaction Cell Pressure - measured directly - S2, R2
3. Sample Gas Pressure - measured directly S1, R1
4. Sample Flow - computed from sample pressure and reaction cell pressure S1, S2
The above pressures and flows are filtered to produce the front panel readings. There is a small
delay after adjustment for a steady reading when observing the TEST functions.
The flow/pressure sensor board consists of 2 pressure sensors and a flow sensor. See Figure 9-8
for a diagram of this board. From these three sensors four values are computed and displayed on
the front panel TEST functions. They are:
1. Ozone Flow - measured directly - S3, R3
2. Reaction Cell Pressure - measured directly - S2, R2
3. Sample Gas Pressure - measured directly S1, R1
4. Sample Flow - computed from sample pressure and reaction cell pressure S1, S2
The above pressures and flows are filtered to produce the front panel readings. There is a small
delay after adjustment for a steady reading when observing the TEST functions.
To adjust the OZONE flow:
1. Go to DIAG mode by pressing SETUP-MORE-DIAG, then select SIGNAL I/O, and press
ENTR. Select OZONE_FLOW by using NEXT-PREV keys.
2. Adjust R3 so that OZONE_FLOW reads 2000 mV. This is the coarse adjustment.
3. Press EXIT to return to the SAMPLE mode. Select the OZONE FL - TEST function. Plumb
a calibrated flow measuring device upstream of the ozone generator (see Figure 9-7). Use the
external device reading to make small adjustments in R3 to dial in correct flow readout on
the front panel.
