Varian 947, Руководство по эксплуатации и обслуживанию

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Models 947, 948 and 960 Leak Detectors Operations and Service Manual
1-7
1 Volume Control Controls the volume of the audible leak rate signal.
2 Display Button Displays the selected reject level of the leak detector
using the 50-segment leak rate bar graph and the
appropriate range exponent.
3 Rough Pump Power
Switch Controls the power to the roughing pump.
4 Detector Power Switch Controls the power to the backing pump and high
vacuum pump.
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.