D397-21-880 Issue G
Page 22
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Operation
4.8.1
Default setup options (all gauges)
All gauges have the following default items on their respective setup screens. (The example below shows the APGM
as the connected gauge).
Figure 18 - Gauge setup screen
Note:
Active Strain Gauges (ASG) are gas independent. Selection of any gas type will give the same pressure
output.
4.8.2
Gauge status messages
Standard status messages are shown in
4.8.3
Active Pirani Gauge (APG)
Note:
For a detailed specification and instructions regarding the use of the APG and APGX gauges refer to the
appropriate Instruction Manual (D021-71-885, D023-71-880 and D023-91-880).
The Active Pirani Gauge (APG) is a gas dependent high-pressure thermal conductivity gauge. The measuring range of
the APG-M and the corrosion resistant APG-MP is 100 mbar to 10
-3
mbar (75 to 7.5 x 10
-4
Torr); the range of the APG-
L is 10 mbar to 10
-4
mbar (7.5 to 7.5 x 10
-5
Torr). All of the gauges will indicate pressure up to 1000 mbar (750 Torr)
at reduced accuracy.
Note:
At pressures above 600 mbar, sensitivity is reduced and TIC displays atmospheric pressure.
Note:
Before the APG is used and periodically thereafter, atmosphere and vacuum calibration should be carried
out in accordance with the directions shown in the Instruction Manual (D021-71-885, D023-71-880 and D023-
91-880).
The APG is set up as per the default gauge setup instructions shown in
above.
Table 9 - Gauge status messages
Diagnostic messages
Description
Not Connected
Indicates that no gauge has been connected to TIC, or if a cable has been
connected, the gauge may not be connected to the other end.
Disconnected
The gauge connection has been removed intentionally or accidentally.
New ID
Indicates that a new gauge has been connected to TIC. The gauge is recognised by
TIC, but must be acknowledged by the user before TIC will allow the gauge to
operate on the system.
Uknw
Indicates that the connected gauge is not recognised by TIC. In this case, TIC will
continue to display the gauge as Uknw and will give an output in volts only.