Teledyne LGA-3500 - Laser Gas Analysis system - Manual (Page 87)

Laser Gas Analyzer Maintenance and Calibration
Teledyne Analytical Instruments 73
tube connector
¦ Õ 6 tube
Figure 6.3 Schematic of the connection of calibration gas transport
tubes
4. Before starting the calibration, turn on the system power and
wait for at least an hour.
Note: The instrument and electronics must be thermally stable. If
the temperature of the sample site (or where the receiver
and transmitter and calibration tube are located) fluctuates,
the stabilization period may be longer than one hour.
5. If you are using the PC service program to calibrate, run the PC
service program. If you calibrate the system with the system
front panel, go to the next step.
6. Start the zero gas flow into the calibration system. Wait until the
gas concentration has stabilized then run the zeroing program in
the PC service program or from the system front panel.
7. Set the optical path length of the calibration tube (refer to the
calibration parameter table that comes with the system). Set the
calibration gas concentration, temperature and pressure. For
increased accuracy, the temperature and pressure of the
calibration gas should be measured directly with temperature and
pressure sensors.
8. Switch from zero gas to span gas (standard gas with a
concentration that is recommended in the calibration parameter
table). Once again, wait until the span gas concentration has