Thermo Scientific 49i, Instruction Manual, Page: 140 / 314

Calibration
Calibration Photometer System Preparation
4-4 Model 49
i
Instruction Manual Thermo Fisher Scientific
1. Turn the calibration photometer on.
2. Turn on the ozonator.
3. Allow the calibration photometer and ozonator to stabilize for one hour.
4. Perform service checks of Chapter 5 “Preventive Maintenance.”
Ozone Loss Test
If the calibration photometer passes the leak test in the “Preventive
Maintenance” chapter, it is highly unlikely that the system is destroying
ozone. If desired, a rigorous test is as follows (this check follows the EPA's
Technical Assistance Document with the appropriate change for a
time-shared, dual cell system). For this test, if the internal ozonator of the
Model 49
i Primary Standard is being used, make sure it is in the manual
mode.
1. Calibrate an ozone analyzer using the calibration photometer. Assume
the photometer is correct.
2. Generate a stable level of ozone and with the calibrated ozone analyzer
measure and note reading as R
m
.
3. Unplug the pump of the calibration photometer from the AC power
source and plug the exhaust line and zero-air inlet line.
4. Connect the calibrated ozone analyzer to the access port on the inlet of
Cell A.
5. From the Service Mode menu, select Intensity Check. From the
Intensity Check menu, select Int B Reference Gas. Wait for a steady
reading and record the intensity as R(a)
input
.
6. Connect the calibrated ozone analyzer to the access port on the inlet of
cell B. From the Service Mode menu, select Intensity Check. From the
Intensity Check menu, select Int A Reference Gas. Wait for a steady
reading and record the intensity as R(b)
input
.