Usage Notes
- The Pirani gauge is a vacuum gauge that uses the thermal conduction of gases, so the pressure display varies depending on the gas type.
The gauge is calibrated with nitrogen or air. If the inside of the vacuum chamber contains other gas or mixed gas, the conversion is required.
- ULVAC Pirani vacuum gauge uses the amount of power change that maintains the filament at a constant temperature, so even if the pressure is the same, the indicated value is affected by the ambient temperature.
- Since the gauge head cable is also part of the circuit, changing the length of the cable will change the resistance value of the circuit, which changes the indicated value. (However, this does not apply to devices with a detection unit circuit on the sensor side.)
- Since the filament is a thin metal wire, vibration or shock may disconnect the filament.
Trouble check lists
1. The meter needle does not deflect when power is turned ON
2. Even if the pressure is changed, the meter needle remains deflected off-scale to the right ( or to the left)
3. The pressure indication does not exceed 3k Pa when atmospheric pressure is measured
4. The needle vibrates and does not indicate a constant value
1. The meter needle does not deflect when power is turned ON
2. Even if the pressure is changed, the meter needle remains deflected off-scale to the right ( or to the left)
3. The pressure indication does not exceed 3k Pa when atmospheric pressure is measured
4. The needle vibrates and does not indicate a constant value