Bacharach H-25C, Инструкция

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H-25C Instruction Manual
Instruction 3015-0216
42
4.3 R-12 Leak Detection
The leak detector sensor for measuring R-134a requires a much greater sensitivity than for
measuring R-12. Since the H-25C has a very sensitive sensor, it generates a very large output for R-
12. This causes any unwanted gas in the atmosphere to have large effects, resulting in disturbances,
and this also affects the service life of the sensor. If the H-25C is used for detecting R-12 leaks then
perform the following calibration procedures.
Note that the LS-20B Leak Standard is required for calibration.
4.3.1 Switch Setting
Perform calibration in manual calibration mode. Set the switches in the setup area as follows :
GAS switch: set to R134a
CAL switch: set to MANUAL
UNIT switches: set to ml/s
ALARM switches: set the leak rate set in the LS-20B
4.3.2 Calibration Procedures
Perform calibration as follows :
(1) Insert the probe into the CAL PORT and provide ON signal for the spring switch. In case of the
S-type probe, the tube for introducing gas must be removed to perform this operation.
(2) After providing ON signal, immediately remove the probe from the CAL PORT and suck in clean
air without pressing any switch. The speaker sounds a tone about seven seconds later, then
calibration starts.
(3) While in search mode, bring the probe tip near the LS-20B PROBE and keep it close until the
value on the display stabilizes.
(4) When the display stabilizes (after about 1 0 seconds ), press the probe switch once (for less than
0.5 sec.). Immediately pull out the probe from PROBE and suck in clean air. Use the reading at
this time for the calibration data.
(5) Verify that the sensor sensitivity displayed on the bar graph area is between 60 and 100%. If it
exceeds 100%, turn the HEATER variable resistor clockwise, and repeat the procedures from (1)
until it lies within the range. If it does not reach 60% (Note), turn the HEATER variable resistor
counterclockwise( generally, turn the knob three or four times more than the factory setting), and
repeat the procedures from (1) until it lies within the range.
Note - CAL FAIL lamp lights when 50% or less