Models 947, 948 and 960 Leak Detectors Operations and Service Manual
3-12
3.4.1 Calibration and Sensitivity Checks
To perform calibration and sensitivity checks:
1. Warm up the 947/948/960 for 30 minutes.
2. Place the test port plug in the test port opening
➅
. Refer to Figure 3-2 on page 3-8.
3. Set the Transfer switch to
AUTO
.
4. Set the Mode switch to
AUTO
. The VENT LED should illuminate.
5. Press the
START
button.
❑
The VENT LED goes off.
❑
The START LED illuminates.
❑
The TEST LED illuminates when test pressure drops.
❑
The START LED goes off (1 second) after TEST LED illuminates.
❑
The Leak Rate range display goes to most sensitive range.
6. Press the
ZERO
button. The ZERO LED turns on briefly.
7. Be sure the TEST LED is on, and press the
STD LEAK
button.
The STD LEAK LED illuminates and the LEAK RATE display should be equal to the
internal calibrated leak as marked inside the hinged top cover.
8. Press
STD LEAK
again to turn it off and continue testing.
The LEAK RATE display should return to the most sensitive decade. If the leak rate
reading is not within 20% of the number on the calibrated leak label, perform an AUTO
CAL.
Summary of Contents for 948
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