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Leak rate ⋅ 10 – INFICON Protec P3000(XL) Helium Leak Detector User Manual

Page 79

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Equipment Settings

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Converting an output
voltage to a leak rate

If the recorder outputs a certain voltage and you want to convert this to a leak rate,
the following formula applies:

(2 is used since one decade is spread over 2 Volts. 3 is used because the trigger
level will always be within the range of 3 to 5 V).

Example calculations:

Trigger

Trigger
exponent

Output
voltage

Leak rate

0.1 oz/yr

-1

5.35V

3 g/a

0

5.60V

6.4V

5 x 10

-4

mbar l/s

-4

2.8V

6.556V

leak rate

10

Trigger

onent

exp

U

3

2

-------------

+

=

10

1

5 35

,

3

2

---------------------

+

1 5oz

,

yr

=

10

0

5 6

,

3

2

------------------

+

20g a

=

10

0

6 4

,

3

2

----------------

+

50g a

=

10

4

2 8

,

3

2

------------------

+

8 10

5

mbarl s

=

10

4

6 55

,

3

2

---------------------

+

1 5mbarl s

,

=