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4 vacuum for vacuu•lan networks – Heidolph ROTAVAC Vario pumping unit User Manual

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Documents are only to be used and distributed completely and unchanged. It is strictly the users´ responsibility to check carefully

the validity of this document with respect to his product. Manual-no.: 999248 / 28/04/2011

Semi-automatic distillation and evaporation

Select function ”

Pump down”.

Start process by pressing key ”START/STOP”.

Observe process. As soon as evaporation starts, press key ”MODE” (switching to ”Vac control”). The

vacuum level is kept constant (at the boiling pressure). Fine tuning of the vacuum value is possible

by turning the selection knob.

Pressing key ”MODE” a second time switches to ”Auto mode” causing the vacuum level to be auto-

matically adapted to changes of the boiling pressure.

alternatively:

Select function ”

Vac control”.

Setting a maximum ”Speed” leads to a faster or slower process.

To set ”Maximum” is usually not necessary because the pressure does not increase at the end of the

evaporation.

Set a value for ”Duration” if the process should automatically be terminated at the end of a definite

time.

Set ”Set vacuum” depending on the solvent and the temperature.

Start process by pressing key ”START”.

Temporary switching to” Auto mode”: Press key ”MODE”. The controller switches to ”Auto mode”.

The setting of the controller does not change due to this switching. After pressing key ”START/STOP”

the controller is in ”Vac control” again.

alternatively:

Fully automatic determination and adaptation of the boiling point (recommended)

Select function ”

Auto mode”.

Start process by pressing key ”START/STOP”.

The function ”Auto mode” allows a fully automatic distillation even if the boiling pressure is unknown.

In case of solvent mixtures the vacuum is reduced until all solvents or volatile components are

evaporated (with respect to the ultimate vacuum of the pump and the bath temperature).

If ”Minimum” is set the controller switches off the pump when the preset vacuum value is reached.

The ”Minimum” should be clearly below the boiling vacuum of the solvent to be evaporated and

above the ultimate vacuum attainable in the apparatus. If the ”Minimum” is set to Auto , the control-

ler automatically switches off the pump at the end of the evaporation (recommended for large solvent

quantities only). The setting of ”Duration” (process runtime) is without effect if the pump is switched

off due to ”Minimum” before ”Duration” is over.

When setting a value for ”Duration” the controller switches off the pump when ”Duration” has passed

even if a preset ”Minimum” is still not reached.

If neither ”Minimum” nor ”Duration” is preset, the process has to be finished by pressing key STOP.

5.7.3 Vacuum for distillation and evaporation (e. g. rotary evaporator)

Select function

VACUULAN.

Set ”Set vacuum” to a pressure value which can be reached in the vacuum network reliably under

consideration of the ultimate vacuum of the pump and the leak rate of the system in case of no

vacuum demand.

Choose the vacuum for switching on the pump again (”Switch on”) in order to ensure sufficient

vacuum for all processes.

Preset ”Delay” if necessary.

Start process by pressing key ”START/STOP”.

5.7.4 Vacuum for VACUU•LAN networks