Vacuum Control - IKA RV 10 control Mode D'emploi

In addition to offering a full range of manual and semi-automatic
evaporation operating modes, the RV 10 control rotary evapora-
tor can also be used for fully automatic and quantity-controlled
evaporation processes. Standard fittings for fully-automatic ope-
ration include a vacuum controller, a cooling water differential
temperature measurement sensor and a cooling water flow rate
meter. The vacuum can be controlled in both two-position and
speed-controlled pumping operation with the help of the integra-
ted vacuum controller. The device is designed for operation with a
cooling water supply system (e.g. laboratory thermostat), but can
also be run off a water supply line. Please refer to the Technical
Data for information on cooling water pressure, temperature con-
stancy, flow rate and local regulations.
We recommend using the RV 10.5001 water regulator valve
when operating directly off a water supply line.
This valve allows the cooling water flow rate to be adjusted and
automatically cuts off the cooling water supply on completion of
the distillation process.
RV 10 control
A vacuum is made in the glassware with the help of a vacuum
pump. The vacuum pump operates at constant speed which ge-
nerally cannot be adjusted.
Once the target value is reached the suction line is interrupted.
The device will fall slightly short of the target value setting due
to the minimum time difference from detection of the pressure
value, the target value comparison for switching the vacuum valve
and the suction line of the vacuum generating system. If the pres-
sure in the system increases again due to the natural leakage rate,
the valve opens the suction line.
The switching frequency and accuracy can be set via the hysteresis
setting.
With the VC 2.4 pump control connected, the power supply to
the pump is also switched on and off accordingly. This reduces the
noise level and increases the service life of the pump membranes
and motor.
The actual value fluctuates in size of the set hysteresis around the
target value.
Automatic boiling point recognition is not accurately possible
when using two-position control.
Schematic view of a two-position vacuum control
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The RV 10.5002 water filter can be used to prevent particles of
dirt passing from the water supply line into the valve mechanism.
If pressure reduction is required, we recommend fitting the
RV 10.5003 pressure regulator valve in the pipe immediately
downstream of the pick-off point.
Automatic volume-dependent distillation: The apparatus
must be brought up to operating temperature. This is achieved by
conducting a test distillation.
RV 10 auto: The rotary evaporator is fitted as standard with
speed control pump, internal venting vale and a pressure measu-
ring chamber.
RV 10 control (for vacuum): The external two-position vacuum
control is also available for the application which in-house vacuum
system is available. Vacuum valve RV 10.4002 must be used.

Vacuum control

RV 10 auto
Imprecision of the two-position control is avoided by using the
speed-vacuum control.
However a vacuum pump with a controlled speed is needed for
speed-vacuum control; the RV 10.4002 vacuum valve is not requi-
red and must not be connected! To do so, connect the vacuum
pump (e.g. IKA Vacstar digital pump) to the port on the rear of
the rotary evaporator.
With this kind of control, the speed of the pump, and therefore
its suction power, is reduced the closer the measured pressure
reaches the target value.
Once the target value is reached, the pump only operates accor-
ding to the leakage rate.
It is possible to achieve quieter operation and more exact vacuum
control.
The speed-vacuum control on the RV 10 is controlled automati-
cally as soon as an appropriate vacuum pump is attached.
Automatic boiling point recognition is possible with this type of
control, i.e. the system reaches and keeps the solvent at its boiling
point in automatic mode.
As it is not necessary to know the boiling point of the solvent
when in automatic boiling point recognition mode (unlike in the
case of volume-dependent distillation), these two operating mo-
des are mutually exclusive.
Schematic view of speed-vacuum control