Glass Bayard-Alpert Ionization Vacuum Gauge, <1 x 10-9 - 1 x 10-3 Torr, 1.0 in. Kovar Metal
The 274006 Glass Bayard-Alpert Hot Cathode Gauge features a single thoria-coated iridium filament, a <1 x 10-9 to 1 x 10-3 Torr vacuum measurement range, and a 1 inch Kovar metal port. 274 Ionization Vacuum Gauges provide good vacuum and pressure measurement at an economical cost. Bayard-Alpert (hot cathode) gauges provide pressure measurement based on the ionization of gas molecules by a constant flow of electrons from a filament. The number of ions created is directly proportional to the density of molecules. The ions are collected and measured by a vacuum gauge controller and converted to pressure based on the sensitivity of the gauge. Specifications
Type
Vacuum Gauge
Sensor Type
Bayard-Alpert Hot Cathode
Vacuum Pressure Range
1.0 x 10-9 to 0.001 Torr
Accuracy
±20% (typical)
Orientation
Any, Vertical preferred
Port Size
1.0 in.
Fitting Type
Kovar Metal
Envelope
Nonex 7720 glass, 2.25 in. (57 mm) OD, 5 in. (127 mm) long
Collector
Tungsten, 0.010 in. diameter
Grid
Refractory Metals
Length
6 in. (152 mm)
Sensitivity
10/Torr
X-ray Limit
3 x 10-10 Torr
Electron Bombardment Degas
100 Watts maximum
Resistance Heated Degas
6.3 to 7.5 VAC at 10 Amps (l2R)
Collector Potential
0 V
Grid Potential
+180 VDC
Filament
Single Thoria-coated Iridium
Filament Heating Current
4 - 6 Amps
Filament Heating Voltage
3 - 5 V
Filament Voltage Potential
+30 VDC
Maximum Bakeout Temperature
450°C
Type
Vacuum Gauge
Sensor Type
Bayard-Alpert Hot Cathode
Vacuum Pressure Range
1.0 x 10-9 to 0.001 Torr
Accuracy
±20% (typical)
Orientation
Any, Vertical preferred
Port Size
1.0 in.
Fitting Type
Kovar Metal
Envelope
Nonex 7720 glass, 2.25 in. (57 mm) OD, 5 in. (127 mm) long
Collector
Tungsten, 0.010 in. diameter
Grid
Refractory Metals
Length
6 in. (152 mm)
Sensitivity
10/Torr
X-ray Limit
3 x 10-10 Torr
Electron Bombardment Degas
100 Watts maximum
Resistance Heated Degas
6.3 to 7.5 VAC at 10 Amps (l2R)
Collector Potential
0 V
Grid Potential
+180 VDC
Filament
Single Thoria-coated Iridium
Filament Heating Current
4 - 6 Amps
Filament Heating Voltage
3 - 5 V
Filament Voltage Potential
+30 VDC
Maximum Bakeout Temperature
450°C
