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MANUAL P/N 316005 REV: B
1.4.1 Instrument Grounding
For safe operation, the Series 316 VGC controller must be connected to an AC power source which includes
a ground wire. This power ground is generally a sufficient safety precaution. A grounding stud is provided on
the rear panel of the power supply module to be uses as a separate earth ground. Ground all metal parts of
your vacuum system separately to power or earth ground. Do not ground the system via a wire to the 316
VGC chassis. Refer to Figure 1-5.
NOTE
: The metal case of the gauge tube does not connect to the controller ground. Electrical connection of
the gauge tube envelope to the system does not cause a ground connection between the system and the
controller.
Figure 1-5 Correct System Grounding
1.5 Operation
1.5.1 Summary of Controls and Indicators
A description of the controls and indicators found on a basic 316 VGC is given in this section. For detailed
instructions pertaining to particular modules, refer to the chapter for that particular module.
1.5.2 Units of Measure
The unit of measure displayed is selectable via switches on the Convectron, thermocouple and capacitance
manometer modules. These units will be indicated on the front panel label when shipped from the factory.
See sections 2.2, 3.2, or 4.2 for instructions on changing units of Convectron, thermocouple or capacitance
manometer module. The pressure units label (#10 of Figure 1-6) is part of the process control channel label
and can be changed by the user if the system of units is changed. Slide the label out from the top.
The pressure is displayed in Torr/millitorr (mbar/mbar x 10
-3
or pascal/pascal x 10
-3
) notation. That is, at
pressures below one Torr, the display shows a 10
-3
exponent, indicating millitorr, while higher pressures
display no exponent, indicating Torr.
