H-25C Instruction Manual
Instruction 3015-0216
26
3. CALIBRATION
The Model H-25C Halogen Leak Detector performs calibration when the detector is first used (including sensor
sensitivity adjustment and sensor replacement) or when " calibration request " appears in A-type measurement
mode. Calibration data are maintained for about three weeks after calibration, then returned to the default
values, after which the instrument must be calibrated again.
The calibration request message appears only in A-type measurement mode; it appears after power-on, then
again after repeated fixed intervals (calibration request interval). The calibration request message will also
appear if the measured value in search mode is at or above the "trigger point"( see Subsection 4.2.1 ) for more
than 20 seconds.
Calibration is performed using a leak standard that provides a freon gas leak of known flow.
There are two calibration alternatives: auto calibration and manual calibration. The auto calibration method
uses a built-in leak standard, and can be used only if the instrument is equipped with the auto calibration
option.
When performing a calibration by the manual method, you must change the "ALARM" (alarm point) setting
value to the leak flow of the leak standard, but this is not necessary in the case of auto calibration.
