Edwards AIM-SI1-NW25, Инструкция по эксплуатации, Страница: 14 / 26

D146-71-880 Issue E
Page 10 © Edwards Limited 2015. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
Operation
4.4 Set-point
Note: The set-point is not used if you connect the AIM Gauge to an Edwards Controller.
To adjust the voltage at which the set-point output signal goes on, turn the set-point potentiometer, which is
accessible through an access hole in the end cap of the gauge: see
Figure 1 . Turn the potentiometer clockwise to
increase the voltage and turn it anticlockwise to decrease the voltage. Refer to Section 4.3 to determine the
operating voltage which corresponds to a given pressure.
The AIM Gauge has an error monitoring facility, which ensures that the set-point output signal is off:

When the gauge is switched off (that is, not enabled)

For 0.5 seconds immediately after the AIM Gauge is switched on

When the pressure output signal is out of range, perhaps because the gauge has failed to strike (ignite)
If required you can adjust the potentiometer so that the set-point operating voltage is < 1.8 V (that is, turn the
potentiometer fully anticlockwise). This ensures that the set-point output signal is permanently off.
If required, you can use the set-point output signal to indicate when the Gauge is operating correctly; adjust the
potentiometer so that the set-point operating voltage is

10 V (that is, turn the potentiometer fully clockwise). If
the gauge is operating normally, the set-point output signal will then be switched on.
Note: If you adjust the set-point operating voltage to > 9.5 V the hysteresis voltage will be > 10 V and the set-
point output signal may not switch off when the pressure rises; if so, the set-point output signal will only
go off when the gauge is switched off (that is, disabled).
Table 2 - Pressure and voltage characteristics for nitrogen and dry air
Pressure (mbar) Output voltage Pressure (torr)
1.0 x 10
-8
2.00 7.5 x 10
-9
2.4 x 10
-8
2.50 1.8 x 10
-8
5.8 x 10
-8
3.00 4.4 x 10
-8
8.1 x 10
-8
3.20 6.1 x 10
-8
1.1 x 10
-7
3.40 8.3 x 10
-8
1.5 x 10
-7
3.60 1.1 x 10
-7
2.1 x 10
-7
3.80 1.6 x 10
-7
2.9 x 10
-7
4.00 2.2 x 10
-7
4.0 x 10
-7
4.20 3.0 x 10
-7
5.4 x 10
-7
4.40 4.1 x 10
-7
7.3 x 10
-7
4.60 5.5 x 10
-7
9.8 x 10
-7
4.80 7.4 x 10
-7
1.3 x 10
-6
5.00 9.8 x 10
-7
1.7 x 10
-6
5.20 1.3 x 10
-6
2.2 x 10
-6
5.40 1.7 x 10
-6
2.8 x 10
-6
5.60 2.1 x 10
-6
3.6 x 10
-6
5.80 2.7 x 10
-6
4.5 x 10
-6
6.00 3.4 x 10
-6
5.6 x 10
-6
6.20 4.2 x 10
-6
6.9 x 10
-6
6.40 5.2 x 10
-6
8.4 x 10
-6
6.60 6.3 x 10
-6