IKA RET control-visc Mode D'emploi page 27

Note:
The user is responsible for ensuring the suitability/function
of the stirring bar decoupling monitoring for the current
conditions: stirring bar, speed, vessel, medium, etc.
Stirring bar decoupling monitoring does not work if the stirring
bar already breaks away before the system has reached the
set target speed!
The higher the torque to be transferred, the more safely the stirring
bar decoupling monitoring works.
In a glass beaker with water, the stirring bar decoupling for a bar
from 40 mm (d=8 mm) upwards can be seen from 300 - 1200 rpm.
Longer stirring bars, larger bar surface areas, e.g. Trika, or higher
speeds increase the torque to be transferred.
Heating
Regulation of the temperature of the medium using PT 100
temperature sensor
When using the PT 100, the selected temperature control mode is
shown on the digital display by the
The set value temperature (2) and
the actual temperature (5) shown on
the display refer to the temperature
of the medium. The heating plate
temperature is limited by the actual
safety circuit temperature (7). The
medium temperature is controlled
by means of a microcontroller. The
medium temperature is measured by
the PT 100 temperature sensor and
is heated up as quickly as possible
without overshooting to the set
temperature. The microcontroller is
capable of adjusting automatically
to the different heating capacities of
various vessels and their contents. As
a result, the heat is distributed in an
optimum fashion with no temperature
drift or ripples.
Regulation of the temperature of the medium using PT 1000
double temperature sensor
Operation with the PT 1000 double
sensor is indicated on the digital
display by the symbol. One
temperature sensor is located in the
heat carrier and the other is located
in the reaction medium. The set
value temperature (2) refers to the
temperature of the medium. The
heat carrier temperature is shown on
the display as an additional current
temperature with the symbol
The actual temperature of the reaction
medium is shown as the actual
temperature (5). The heating plate
temperature (and therefore the heat
carrier temperature) are limited by the
actual safety circuit temperature (7).
The reaction medium temperature is
limited by the set temperature limits (carrier/reaction temperature
limit).
symbol.
.
Intermittent mode
Intermittent mode consists of regular, cyclical interruption of
the stirring function. The run time and interval can both be set.
When switching on the device, the time for each is displayed if
intermittent mode is activated.
Speed limit
The "Speed limit" menu allows the user to set the desired maximum
upper speed limit for the stirrer. The initial setting is the maximum
permissible speed of the stirrer. If the user changes this setting, the
Wireless Controller saves the new value for future stirring tasks.
If the "Speed limit" has been changed, then the speed can be ad-
justed only within the new range.
Control method
The user is able to set the device to three different methods
depending on their specific needs. The selected temperature
control method is displayed alongside the symbol (11).
Fast PID: combines the advantages of the PID and two-point
methods (very fast
heating and high
accuracy; possible
overheating).
Accurate PID: For use with very sensitive materials which need to
be handled
carefully.
Advantages:
• very accurate warming
of the liquid
• no exceeding the target
temperature
Disadvantages:
• slow heating operating
Two-point:
For media which is not too sensitive.
Advantages:
• Heating much more
rapid than PID
Disadvantages:
• Possible overheating of
up to 10 K
Limits
In order to ensure that neither the medium nor the carrier fluid
overheat, the user can set separate temperature limits.
Medium limit:
The "Medium limit" menu allows the user to set the desired
maximum temperature limit for the medium.
Carrier limit:
The "Carrier limit" menu allows the user to set the desired
maximum temperature limit for the carrier fluid.
Limit information:
The "Limit information" menu shows the set medium limit and
carrier limit.
T
Set
T
Set
t
t
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