D397-01-880 Issue E
Page 30
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Operation
Figure 22 - Gauge setup screen WRG
Note:
If the Pirani sensor is replaced (see WRG instruction manual D147-01-885) it may initially fail to indicate
pressures less than 1 x 10
-3
mbar (7.5 x 10
-4
Torr). In this case a manual vacuum calibration is required.
Pump down to 1 x 10
-5
mbar (7.5 x 10
-6
Torr) or below before performing the CAL operation as described in
the instruction manual.
WRG has an built-in error monitoring capability. (Refer to
).
Table 24 - Error/diagnostic monitoring WRG
Diagnostic messages
Description
Over Range
(Gauge output >10.600 V)
Indicates that there is a fault with the gauge and it should be replaced.
Not Struck
(Gauge output = 1.300 V)
Indicates that the magnetron part of the gauge has not struck.
The gauge tube should be inspected for signs of contamination or debris. If the anode
and cathode are not bright, the gauge should be cleaned as described in the WRG
instruction manual.
Striker Fail
(Gauge output = 1.200 V)
Indicates that the striker filament has broken.
The electrode assembly (D147-01-802) should be replaced as described in the WRG
instruction manual.
Mag Fail
(Gauge output = 1.100 V)
Indicates that the magnetron part of the WRG has shorted out. This could be because
of contamination or a foreign body. The WRG should be cleaned as described in the
instruction manual.
If this fails to rectify the fault, the WRG should be serviced and the electrode
assembly (D147-01-802) replaced as described in the instruction manual.
Filament Fail
(Gauge output = 1.000 V)
Indicates that the Pirani element of the gauge has failed. The most likely fault being a
broken filament. The WRG should be serviced as described in the instruction manual.
Under Range
(Gauge output <0.950 V)
Indicates that there is a fault with the gauge and the electronics module should be
replaced.
