9
BÜCHI
Vacuum Controller
V-800/V-805
3.2.6.2 Automatic hysteresis (dP = A)
The hysteresis is automatically adjusted to the input set point
and is 5 % of the set point, but a minimum of 2 mbar.
Example: set point is 400 mbar, automatic hysteresis
The system pressure is reduced to 400 mbar, the vacuum
source is turned off
The system pressure increases by 20 mbar
The vacuum source is turned on and the system pressure
is evacuated again to 400 mbar
3 Functions
Automatic hysteresis
20 mbar
400 mbar
1
2 +
t
P
0
0
420 mbar
3
