24
tina56e1-f (2015-09)
2.2
Gas Type Dependence
Indicated pressure (gauge calibrated for air)
10
2
10
1
10
0
10
–1
10
–2
8
6
4
2
10
–3
10
–4
2
4 6
10
–3
2
4 6
10
–2
2
4 6
2
4 6
10
0
2
4 6
10
1
10
–1
10
–4
p
eff
[mbar]
2
4 6
10
2
2
4 6
10
3
10
3
p [mbar]
2
Air, O
2
, CO, N
2
He
Ar
8
6
4
2
8
6
4
2
8
6
4
2
8
6
4
2
8
6
4
2
8
6
4
2
4
2
Capacitive
diaphragm
sensor
Crossover
range
Pirani
sensor
Calibration factors
valid for Pirani pressure range below 1 mbar
p
eff
= C × indicated pressure
Gas type
Calibration
factor C
Gas
type Calibration
factor C
He
Ne
Ar
Kr
Xe
0.8
1.4
1.7
2.4
3.0
H
2
air, O
2
, CO, N
2
CO
2
water vapor
Freon 12
0.5
1.0
0.9
0.5
0.7