Thyracont VSH87E, Руководство по эксплуатации

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39
In such cases it is appropriate to clean the anode of the sensor from such depo-
sited material and adsorbed gas molecules by degassing. This is done at pressu-
res below 2.0x10
-6
mbar by ohmic heating of the anode to temperatures around
800
◦
C.
The parameter is used to control the degas procedure and query the status.
»0«: Degas off
»1«: Degas on
The degas procedure will stop automatically after approx. 3 minu-
tes, but can be cancelled any time. While the sensor is degassing
the red status LED is flashing slowly in red color.
Sensor Transition (ST)
By default the VSH performs a continuous transition between Pirani and hot ca-
thode range whereupon an assimilation of the sensor signals is carried out.
In order to adapt the performance of the transducer to the requirements of the
vacuum process the following options can be configured by means of parameter
»Sensor Transition« (ST):
»0«: no transition, but direct switch-over between Pirani and hot ca-
thode sensor at 4.0x10
-4
mbar
(hot cathode on at 4.0x10
-4
mbar / off at 6.0x10
-4
mbar)
»1«: continuous transition in the range 1.0 ... 2.0x10
-3
mbar
(hot cathode on at 3.0x10
-3
mbar / off at 4.0x10
-3
mbar) (default)
»2«: continuous transition in the range 2.0 ... 5.0x10
-3
mbar
(hot cathode on at 8.0x10
-3
mbar / off at 9.0x10
-3
mbar)
D[p]:
∗
no transition, but direct switch-over between Pirani and hot ca-
thode sensor at pressure p
F[p1] T[p2]:
∗
continuous transition in the range p1 ... p2
Value range: p, p1, p2: 4.0x10
-4
... 1.0x10
-2
mbar
∗
) Not accessible via EtherCAT
Enable/Disable Hot Cathode - Cathode Control (CC)
For certain vacuum processes it may be favoured to suppress the automatic start
of the hot cathode sensor, which is usually controlled by the transducer electronics.
Therefore it is possible to disable the hot cathode by software comand »Cathode
Control« (CC):
VSH-EtherCAT-200116