INFICON VSC150A absolute switch, passiv - Manual (Page 18)

max. turning the adjusting screw (6/2) clockwise.
2.5.4 Automatic Venting of a Vacuum Chamber
to a Slight Overpressure
Assembly as in Fig. 9.
Loop the control circuit of the venting valve via the break
contact of the switching amplifier relay, terminals 12 and
13 (see Fig. 5). The switching pressure can be raised by
20 mbar max. above atmospheric pressure by turning
the adjusting screw (6/2) clockwise.
2.5.5 Differential Pressure Monitoring, Positive
and Negative Going
In an annealing plant with „holding vacuum“ pump down
and venting of the annealing pot and the vacuum fur-
nace must be regulated so that the differential pressures
in both directions will not exceed 10 mbar (Assembly as
shown in Fig. 10).
Starting from the basic adjustment set the two Vacuum
Switches by turning the adjusting screw (6/2) clockwise
so that at a pressure of 10 mbar in the reference cham-
ber against the pressure in the sensing chamber the
switch contact opens by flexing of the diaphragm. Con-
trol venting valves and pump valves each via the break
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tina42e1 (2005-03) VSC150.ga
tina42e1 (2005-03) VSC150.ga
max. turning the adjusting screw (6/2) clockwise.
2.5.4 Automatic Venting of a Vacuum Chamber
to a Slight Overpressure
Assembly as in Fig. 9.
Loop the control circuit of the venting valve via the break
contact of the switching amplifier relay, terminals 12 and
13 (see Fig. 5). The switching pressure can be raised by
20 mbar max. above atmospheric pressure by turning
the adjusting screw (6/2) clockwise.
2.5.5 Differential Pressure Monitoring, Positive
and Negative Going
In an annealing plant with „holding vacuum“ pump down
and venting of the annealing pot and the vacuum fur-
nace must be regulated so that the differential pressures
in both directions will not exceed 10 mbar (Assembly as
shown in Fig. 10).
Starting from the basic adjustment set the two Vacuum
Switches by turning the adjusting screw (6/2) clockwise
so that at a pressure of 10 mbar in the reference cham-
ber against the pressure in the sensing chamber the
switch contact opens by flexing of the diaphragm. Con-
trol venting valves and pump valves each via the break
SV SV
VSC 150
R
VSC 150
M
R M
Oven
Crucible
Fig. 10 Differential pressure monitoring, positive and
negative going
VSC 150
M
R
SV
Fig. 9 Automatic venting between atmospheric pressure
and + 20 mbar
SV SV
VSC 150
R
VSC 150
M
R M
Oven
Crucible
Fig. 10 Differential pressure monitoring, positive and
negative going
VSC 150
M
R
SV
Fig. 9 Automatic venting between atmospheric pressure
and + 20 mbar