INFICON BPG402-Sx ATM to Ultra-High Vacuum Gauge - Manual (Page 48)

48
tina46e1-a (2010-03) BPG402.om
Pressure indicated (gauge adjusted for air, Pirani-only mode)
10 2
8
6
4
2
10 1
8
6
4
2
10 0
8
6
4
2
10 –1
8
6
4
2
10 –2
8
6
4
2
10 –3
p (mbar)
p
eff
(mbar)
10 –3 2 4 6 10 –2 2 4 6 10 –1 2 4 6 10 0 2 4 6 10 1 2 4 6 10 2
H
2
He Ne
Xe
Ar
Freon 12
Air
O2
CO
N2
Kr
CO
2
Indication range
above 10
-2 mbar
H
2
O
vapor
The gas type dependence in the pressure range 10 -2 … 1 mbar (Pirani pressure
range) can be compensated by means of the following formula:
p
eff
= C × indicated pressure
where Gas type Calibration factor C
Air, O
2
, CO 1.0
N
2
0.9
CO
2
0.5
Water vapor 0.7
Freon 12 1.0
H
2
0.5
He 0.8
Ne 1.4
Ar 1.7
Kr 2.4
Xe 3.0
(The above calibration factors are mean values)
B: Gas Type Dependence
Indication range
above 10
-2
mbar
Calibration in pressure range
10
-2
… 1 mbar