Edwards AIGX-S-DN16CF, Инструкция по эксплуатации

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OPERATION
D048-50-880 Issue E
4 OPERATION
4.1 Enable and Disable the AIGX
CAUTION
The gauge should not be operated at pressures higher than 5 x 10
-2
torr (6.6 x 10
-2
mbar). Operating the AIGX
at high pressures may reduce the lifetime of the filament.
If you are using the AIGX with a Controller, refer to the Controller instruction manual for details of how to enable
the AIGX. Alternatively, to enable (switch on) the AIGX, connect pin 7 to pin 2. To disable (switch off) the AIGX,
disconnect pin 7 from pin 2.
When the AIGX is enabled, the output signal will remain at 9.0 V whilst the emission current is being stabilised. This
will take typically 5 seconds (may be longer at lower pressures). After this time the output signal will indicate
pressure. If an error occurs, then the output signal will indicate the error.
4.2 Pressure Measurement
If you are using an AIGX with a Controller, the pressure measurement is shown on the Controller display. Otherwise,
convert the output signal to pressure using the following equation:
P = 10
(V - 10)
torr
P = 10
(V - 9.875)
mbar
P = 10
(V - 7.875)
Pa
where V is the measured voltage in volts. Refer to Figure 4 . This formula is valid for the range 0.7 V to 8.7 V.
WARNING
Do not use the AIGX to measure the pressure of explosive or flammable gases or mixtures.
WARNING
During operation, the surface of the ion gauge tube might become hot. To avoid risk of injury, do
not touch the tube whilst the gauge is operating. Switch off the gauge and allow to cool down for
few minutes before handling.
WARNING
Disconnect the electrical supply cable from the AIGX before you remove the AIGX from the vacuum
system. High voltages are generated inside the AIGX.