Gas Dependency - Edwards AIM-S-NW25 Instruction Manual

NRA737880 Issue E
Figure 1 - General View of the AIM Gauge (showing NW25 flange)
1.
2.
3.
An 8-way electrical connector socket on the AIM Gauge
AGC, AGD or electrical supply and voltmeter. Electrical cables fitted with suitable connector plugs are available as
accessories.
A gauge identification signal is available on the electrical connector; this signal is used by Edwards AGCs to identify
which type of Active Gauge is connected.
The AIM Gauge has self-monitoring fault detection circuits. When these circuits detect that the AIM Gauge is not
operating correctly, an error signal is set; this error signal is available on the electrical connector. The device which
sets the error signal is a FET transistor which acts like a switch. When no error is detected, the output of the transistor
is on (closed or low impedance). When the fault detection circuits detect an error, the transistor output changes to
off (open or high impedance).
Note:
If you use an Edwards AGC controller or AGD display, the AIM Gauge error signal is not used.
1.3

Gas dependency

The ionisation of the gas in the vacuum system is dependent on both the pressure and the physical properties of the
gas. Therefore, the output signal of the AIM Gauge is gas dependent.
The output signal voltage to pressure conversions in
Calibration graphs for use with argon, neon, krypton, helium and carbon dioxide are available on request; contact
your supplier or Edwards.
Page 2
End-cap
Body tube
Cable connector plug
(Figure
Table 2
Edwards and the Edwards logo are trademarks of Edwards Limited.
4. Vacuum flange
5. Magnet housing
6. AIM Gauge connector socket
1, item 6) is used to connect the AIM Gauge to your
apply for nitrogen and dry air.
© Edwards Limited 2020. All rights reserved.