Varian 960, Руководство по эксплуатации и обслуживанию

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Models 947, 948 and 960 Leak Detectors Operations and Service Manual
1-20
5 System Pressure
Bar Graph Displays system pressure monitored at the inlet of the spectrometer
tube on a 20-segment bar graph. The green portion of the graph
indicates normal operating vacuum level.
6 Transfer to Fine
Test Switch Holds the leak detector in gross leak mode in the NO position. In the
AUTO position, it transfers into fine test mode.
7 Display Set Point
Button Displays the transfer-pressure set point on the Test Port Pressure bar
graph.
8 Test Port
Pressure Bar
Graph Displays the test port pressure as measured by a thermocouple
gauge mounted near the test port. Used as an indicator to help
prevent damage to the detector due to over-pressure situations.
9 Leak Rate
Exponent Display Indicates the leak rate range exponent in a two-digit numeric display.
Capable of showing 10
−
11
range to 10
0
range in atm cc/sec. The
RANGE EXPONENT is also used to display the error condition code.
10 Leak Rate
Mantissa Bar
Graph A 50-segment bar graph. The left most segment indicates 0.0 and is
on at all times.
11 Leak Rate Over
Indicator Goes on when the upper limits of the Leak Rate scale have been
exceeded.
12 Auto/Man Mode
Switch Selects automatic ranging or manual ranging. When in the AUTO
position, the display starts each test sequence in the least sensitive
range, and ranges down to the most sensitive range. When in the
MAN position, the operator selects a single range to display the range
manually.
13 Smaller/Larger
Exponent
Selection Buttons When Manual Range changing is selected:
❑
SMALLER decreases the leak rate exponent.
❑
LARGER increases the leak rate exponent.
Holding the SMALLER or LARGER button down for more than
3 seconds (wait for the exponent to begin flashing) stores the value of
the manual range exponent in EPROM. The range changes one
decade each time a button is pushed.
14 Start Button Press to initiate test mode.
15 Vent Button Press to initiate vent mode. This allows a test device to be connected
to the 947/948/960 for leak detection.
16 Zero Button Press to initiate auto-zero sequence. The leak detector automatically
zeroes a negative signal.
17 Std Leak Button Press to initiate Std leak check. Opens the standard leak test valve so
that the calibrated leak can be measured to check the leak detector.