APPENDIX
- 23 -
Causes of deviation from measurement accuracy
Ambient temperature
The indication of the Pirani gauge varies with the ambient temperature of the sensor head.
Gas measured
Since the Pirani gauge is a molecular density measuring vacuum gauge, the indication of the
gauge varies with the type of gas (difference in thermal conductivity). The Model GP-1G(RY)
has been adjusted with nitrogen gas and its indication is a value converted to nitrogen.
Contamination of sensor head
The indication will be affected if the sensor head filament is contaminated with foreign matter.
To Next Page