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VACUULAN function
➨
Optimizes vacuum control for vacuum networks
(e.g., VACUUBRAND VACUU•LAN)
➨
Permits on-demand operation of a speed-controlled pump
(NT VARIO/VARIO-B)
Preselections
+
Use the selection knob to select the parameters.
+
Set vacuum
(the lower switch-off value): If the pressure drops below
the ”
Set vacuum
”, a time-meter starts to run and the motor speed is re-
duced. When the pressure exceeds the ”
Set vacuum
” pressure again,
the time meter is reset. If the ”
Set vacuum
” is not reached within 100
hours, the controller signals an error.
The ”
Set vacuum
” is adjustable in the range of 1-795 Torr (1-1060
mbar).
+
Switch on
(the higher switching value): If the pressure exceeds this
pressure, pumping down starts again.
The ”
Switch on
” pressure is adjustable in the range of 2-795 Torr (2-
1060 mbar) (at the least 1 Torr (mbar) higher than the ”Set vacuum”).
In the event of a sudden high-pressure spike, pumping starts again
even if the ”
Switch on
” pressure has not been reached (pressure in-
crease control).
+
Delay:
If the vacuum is below ”
Set vacuum
” for longer than the ”
Delay
”
time, the pump is stopped. Pumping starts again in the event of a rapid
pressure increase or if the ”
Switch on
” level is exceeded.
The ”
Delay
” is adjustable in a range of 1-300 minutes or can be set to
”Off” (”Off” means that the coolant valve closes immediately when the
process stops.).
