Pfeiffer Vacuum ASM 310 - Formulas

12.2.5 Formulas
Mantissa (1/10 V)
The “Mantissa” output corresponds with the leak rate mantissa.
Formula U = Voltage measured (V) on analog output
Mantissa = U
Examples ● U = 3.5 V -> Mantissa = 3.5
● U = 6.9 V -> Mantissa = 6.9
Exponent (0/10 V)
The “Exponent” output coresponds with the leak rate exponent.
● The Exponent increases by 1 V per decade.
● The starting decade corresponds withe 10 V.
Formula U = Voltage measured (V) on analog output
D
0
= Low decade for 0 V
Exponent = 10 - U + D
0
Examples Example 1
Low decade at 10
-12
(10 V = -12) -> D
0
= -12
● U = 7 V -> Exposant = 10 - 7 - 12 -> Exposant = -9
● U = 2 V -> Exposant = 10 - 2 - 12 -> Exposant = -4
Example 2
Low decade at 10
-10
(10 V = -10) -> D
0
= -10
● U = 7 V -> Exponent = 10 - 7 - 10 -> Exponent = -7
● U = 2 V -> Exponent = 10 - 2 - 10 -> Exponent = -2
Logarithmic (0/10 V)
The “Logarithmic” output corresponds with the leak rate value.
● The leak rate increases by 1 V per decade.
● The starting decade corresponds with 0 V.
Formula U = Voltage measured (V) on analog output
D
0
= Low decade for 0 V
Mantissa = 10
(U - Valeur entière (U)
Exponent = Integer value (U) + D
0
Leak rate = Mantissa x 10
Exposant
Appendix
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