MKS 20340-341-T1, Инструкция по эксплуатации

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6 Convectron Gauge Module
53
Series 340 Vacuum Gauge Controller
Instruction Manual - 340005 - Rev. D
More precise control may be achieved by fixing the system pressure at the desired auto turn-ON
pressure, and adjusting the potentiometer slowly until the gauge turns ON.
To disable the auto turn ON function, adjust the CG auto turn-ON potentiometer counterclockwise
to the OFF position.
6.4 Process Relay Turn ON
Depending on the switch position of the two internal selector switches shown in Figure 6-1, either
CG "A" or CG "B" can be used to control the process relay. The process relay turn ON occurs when
the selected CG pressure drops below the setpoint defined by the process relay adjust potentiometer
(see Figure 6-2). The process relay will also automatically turn OFF when the pressure rises slightly
above the setpoint. To disable the process relay, adjust the process relay turn-ON potentiometer
(Figure 6-2) completely counterclockwise to the OFF position.
6.4.1 Setting the Internal CGB & CGA Switches
CG "B" Select Switch - See Figure 6-1.
When the switch is in the ON position, Convectron Gauge B is selected as the controlling
gauge for the process relay.
CG "A" Select Switch - See Figure 6-1.
When the switch is in the ON position, Convectron Gauge A is selected as the controlling
gauge for the process relay.
6.5 Process Relay Turn ON Indicator
The process relay ON indicator LED will illuminate anytime the process relay is energized.
6.6 Gauge Zero and Atmospheric Pressure Calibration
Each Convectron gauge is individually computer-calibrated for N
2
. Adjustment of the zero should
not be necessary unless readout accuracy is required below 1 x 10 –3 Torr. Adjustment of the
atmospheric indication should not be necessary unless compensating for long cables or variations
in mounting orientation. The Convectron gauge has a stable, temperature compensated design and
each Controller is calibrated to provide accurate readout of N
2
pressure with any gauge when it is
properly installed with the gauge axis horizontal.
Calibrations are made using the potentiometers accessed on the front panel of the Convectron
Gauge module. See Figure 6-2.
Failure to use accurate pressure conversion data for N
2
or air to other gases can
cause an explosion due to over pressurization.
If the controller will measure any gas other than N
2
or air, before connecting the
controller to system control devices, adjust pressure outputs for the process gas that
will be used. See Section 4.3 beginning on page 35 for detailed information on gases.