4 Description of function
18
V-850 / V-855 Operation Manual, Version E
4 .2 .1
Manual mode
The Manual mode serves to maintain and control a preset pressure. The pressure setpoint can be
adjusted by means of the selection knob when the pump is running or, before operation, via the corre-
sponding menu by pressing the menu button
P Set
.
4 .2 .2
Timer mode
The Timer mode serves to control the pressure over a predefined time interval. When the time interval
is over, the process stops.
4 .2 .3
AutoDest mode (V-855 only)
The AutoDest mode serves to carry out an automatic distillation based on the temperature differences
within the condenser. Thanks to the AutoDest probe mixtures can be distilled gently and automatically.
The redistillation will also be considered.
4 .2 .4
EasyVac mode (V-855 only)
The EasyVac mode serves to carry out an automatic distillation based on the vapor pressure of the
solvent. The process is started at the push of a button. The start point of the distillation will be identi-
fied automatically. Then the pressure is adapted according to the vapor pressure curve and the end
point of the distillation is determined. Based on sophisticated algorithms the process is executed in a
robust, gentle way. This mode is suited for distilling single solvents.
NOTE
The EasyVac mode only works with a speed controlled Vacuum Pump V-700 / V-710.
1
2
p
t
a
Detection start of distillation
b
Detection end of distillation
4 .2 .5
Gradient mode (V-855 only)
The Gradient mode serves to define up to 15 programs with up to 20 steps each. For a description of
how to define programs, see chapter 6.7.3.
4 .2 .6
Repeat mode (V-855 only)
The Repeat mode serves to reproduce a distillation. The pressure course of the last manual or auto-
matic distillation can be saved and reused as setpoint settings to supply optimum process conditions.
