Ideal Vacuum XactGauge XGC-321 Convection-Enhanced Pirani Sensor Gauge, 1/8” MNPT

The Ideal Vacuum XactGauge XGC-321 Convection-Enhanced Pirani Gauge is a robust, yet inexpensive thermal conductivity sensor that, in combination with our XactGauge XGC-320 Convection-Enhanced Pirani Gauge Controller, obtains accurate pressure measurements in the range of 1x10^-4 to 1000 Torr. Typical accuracy (N2) is ± 2.5% from 400 to 1000 Torr, ± from 1x10^-3 to 400 Torr and 0.1 mTorr resolution from 1x10^-4 to 1x10^-3 Torr.

Thermal conductivity gauges measure pressure indirectly by sensing the loss of heat from a sensor to the surrounding gas. The higher the pressure of the gas, the more heat is conducted away from the sensor. Pirani thermal conductivity gauges maintain a sensor (usually a wire) at a constant temperature and measure the current or power required to maintain that temperature. A standard Pirani gauge has a useful measuring range of about 10^-4 Torr to 10 Torr. Convection-enhanced Pirani gauges take advantage of the convection current inside the sensor to extend the pressure measurement range to just above atmosphere.

Our XactGauge XGC-321 Convection-Enhanced Pirani Sensor Gauge is available with any of eight (8) different flange sizes including:

The Ideal Vacuum XactGauge XGC-321 Convection-Enhanced Pirani Gauge has several advantages over other similar devices:

The temperature compensation coil in our Sensor is mounted outside the vacuum enclosure, and there is no polyimide coating inside. So, it is not susceptible to absorbing condensable vapors.

Compared to other similar gauges, the XactGauge XGC-321 Sensor is physically smaller because it doesn’t use an internal mandrel assembly. This reduces the number of parts and welds in the unit which makes it less expensive while making it less prone to failure due to vibration. There is 1/3 less internal surface area and 2/3 less volume than comparable offerings, so outgassing is substantially decreased and response time to pressure changes is faster as well.

The XactGauge XGC-321 Sensor cable has a male DB9 cable connector which connects to our XGC-320 Controller, and is compatible with other manufacturer’s controllers and cables, such as the Granville-Phillips 475.

When measuring gases other than Nitrogen/Air, accurate correction at the controller must be made for the difference in thermal conductivity between nitrogen and the gas in use, particularly at pressures above 1 Torr. DO NOT USE for explosive, corrosive or toxic gases.