Teledyne BDS-3960 - Oxygen analyzer - Manual (Page 24)

Operational Theory BDS 3960
Teledyne Analytical Instruments 24
hydrogen, it reads 100% lower. For example, when the
float ball in the flowmeter is at 0.5 SLPM, the actual flow
rate of hydrogen is about 1 SLPM.
The BDS oxygen sensor can tolerate exposure to acidic gases. Up
to 0.2% CO
2
has no effect to ppb level oxygen measurement.
2.2.7 Stability
The BDS sensor is essentially drift free. Typically a BDS sensor
requires no re-calibration over an entire year period. However, there
may be some intrusion to the zero during the maintenance. See next
section for details.
2.2.8 Maintenance
The only maintenance required on the BDS sensor is to replenish
distilled or de-ionized water every three to four months. It is not
necessary to take the analyzer out of service while adding water to the
sensor but caution should be taken to avoid spilling water on the PC
boards or other area inside the analyzer.
Figure 2.5: Adding DI Water to the BDS Sensor