Models 947, 948 and 960 Leak Detectors Operations and Service Manual
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3.14.1 Auto Ranging
To use auto ranging for outside-in testing:
1. Press the
VENT
button. Securely attach the new unit under test to the test port while the
947/948/960 is in VENT mode.
❑
The TEST LED goes off.
❑
The VENT LED illuminates.
2. Select the
AUTO
(Figure 3-9) position of the AUTO/MAN MODE switch in the
Leak Rate Range section.
Figure 3-9
Location of AUTO/MAN MODE Switch
3. Press the
START
button.
❑
The VENT LED goes off and one second later, the START LED illuminates.
❑
The TEST LED illuminates.
❑
The START LED goes out.
❑
The LEAK RATE range exponent goes to the most appropriate range.
4. Introduce helium to the unit under test.
The 947/948/960 automatically traces the under test helium signal up range through the
Reject Set Point. If larger than the pre-set Reject value, the leak rate signal reads this
maximum level. The REJECT LED lights up.
