© Edwards Limited 2016. All rights reserved.
Page 29
Edwards and the Edwards logo are trademarks of Edwards Limited.
Operation
D397-01-880 Issue E
AIGX has an built-in error monitoring capability. (Refer to
).
4.8.9
Wide Range Gauge (WRG)
Note:
For a detailed specification and instructions regarding the use of the WRG, refer to the instruction manual
(D147-01-885).
The WRG is a combined Pirani and inverted magnetron gauge in a single compact unit. The WRG measures pressure
from atmosphere down to 1 x 10
-9
mbar (7.5 x 10
-10
Torr). The WRG is gas dependent and has a log/linear output in
the range 2-10 V d.c. The Pirani part of the gauge measures from atmosphere to 1 x 10
-3
mbar (7.5 x 10
-3
Torr) while
the inverted magnetron measures from 1 x 10
-2
down to 1 x 10
-9
mbar (7.5 x 10
-3
to 7.5 x 10
-10
Torr). Output from
both sensors is used to determine pressure between 1 x 10
-2
and 1 x 10
-3
mbar (7.5 x 10
-3
and 7.5 x 10
-4
Torr).
WRG has menu options in addition to those shown. (Refer to Default setup options (all gauges)
. (Refer
).
Table 22 - Error/diagnostic monitoring AIGX
Diagnostic messages
Description
Over Range
(Gauge output >9.800 V)
Indicates that there is a fault with the gauge and the electronics module should
be replaced.
Over Pressure
(Gauge output = 9.700 V)
Indicates that the gauge has automatically shut down, because of pressure
rising above 6.6 x 10
-2
mbar (5 x 10
-2
Torr).
Reduce pressure and re-enable the gauge.
Emission Error
(Gauge output = 9.500 V)
Indicates that either the filament is broken (switch over) or gauge was enabled
at too high a pressure – reduce and re-enable.
Electrical supply is out of spec – check the cables (length and cross section).
Under Range
(Gauge output <0.025 V)
Indicates that either the gauge internal fuse has blown or there is a fault with
the gauge. The fuse should be replaced as described in the AIGX instruction
manual and if the fault persists, the electronics module should be replaced.
Initialising
Indicates that the gauge is establishing an emission current. This usually takes
about 5 seconds.
Table 23 - Setup options WRG
Menu option
Description
Calibrate
Allows the user to perform the atmosphere and vacuum adjustment on the WRG.
Connect the WRG to TIC and allow it to operate at atmospheric pressure for at least 10
minutes.
'Scroll' to 'Calibrate' and press 'Select'.
'Command Sent' appears for 1 s to confirm instruction has been carried out.
The WRG will automatically perform a Pirani sensor vacuum setting every time it is
pumped down below 1 x 10
-4
mbar (7.5 x 10
-5
Torr).
