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4.2
Display
4.2.1 General
The Gas Check LCD matrix display is arranged to show the leak rate and other relevant status
information in a consistent fashion during the normal use and also during user changes to the
settings of the application.
·
In normal use the upper portion of the LCD matrix is used for a large size digital representation
of the leak rate (see Section 4.2.2) and status information is shown as symbols (see section
4.2.3) appearing in the lower portion.
·
In response to Gas Check key presses, written text will appear across the middle of the matrix
display, giving user confirmation of the changes to settings, while status symbols will also change
consistently.
Examples are
Zeroing detector
Nozzle On
Peak hold On
4.2.1 Leak rate indication
Leakage is displayed as a single (signed) digit x 10 (signed) range for ease of interpretation and
calibration.
[Note that some gases (eg CO2) may cause a negative leak indication after Gas Check zeroing in
clean air.]
Examples are
Leak rate for a positive gas:
5 x 10 -5 ml/s
Leak rate for a negative gas
- 3 x 10 -4 ml/s
Gas
Gas Group
Positive/Negative
H
2
0
Positive
He
0
Positive
R12
1
Negative
R1301
1
Positive
R134a
1
Negative
SF
6
1
Negative
R22
1
Negative
CO
2
2
Negative
CH
4
2
Positive
Ar
2
Negative
R11
3
Positive
O
2
4
Positive
Note that for the named gases the response of the Gas Check 5000is series after zeroing
will be only permitted in the same sense as for that named gas, ie positive for helium,
negative for R134a.
