INFICON MPG40x ATM to Ultra-High Vacuum Gauge - Manual (Page 29)

tina48e1-b (2008-10) MPG400-401.om
29
Appendix
p = 10 1.667U-d
⇔ U = c + 0.6log
10
p
p U c d
[mbar]
[Torr]
[Pa]
[V]
[V]
[V] 6.8
6.875
5.6
11.33
11.46
9.333
where p pressure
U measuring signal
c, d constant (pressure
unit
dependent
valid in the range 5×10 -9 mbar < p
3.8×10 -9 Torr < p
5×10 -7 Pa < p
<1000 mbar
<750 Torr
<1×10
5 pa
1E+04
1E+02
1E+00
1E–02
1E–04
1E–06
1E–08
0.0 0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 8.5 9.5 10.5
sen
sor
er
ror
un
der
ra
nge
sen
sor
er
ror
ove
rr
ang
e
Pa
mbar
torr
Measuring signal U [V]
Pressure p
Meas. signal U [V] Pressure p [mbar] Pressure p [Torr] Pressure p [Pa]
<0.5 Sensor error
0.5 … 1.82 Underrange
1.82
2.0
2.6
3.2
3.8
4.4
5.0
5.6
6.2
6.8
7.4
8.0
8.6
5.0Ч10 -9
1.0Ч10 -8
1.0Ч10 -7
1.0Ч10 -6
1.0Ч10 -5
1.0Ч10 -4
1.0Ч10 -3
1.0Ч10 -2
0.1
1.0
10
100
1000
3.8Ч10 -9
7.5Ч10 -9
7.5Ч10 -8
7.5Ч10 -7
7.5Ч10 -6
7.5Ч10 -5
7.5Ч10 -4
7.5Ч10 -3
7.5Ч10 -4
0.75
7.5
75
750
5.0Ч10 -7
1.0Ч10 -6
1.0Ч10 -5
1.0Ч10 -4
1.0Ч10 -3
1.0Ч10 -2
0.1
1.0
10
100
1000
1.0Ч10 4
1.0Ч10 5
8.6 … 9.5 Overrange
9.5 … 10.5 Sensor error (Pirani defective)
A: Measuring Signal vs.
Pressure
Conversion formulae
Conversion curves
Conversion table