Controlling The Medium Temperature - IKA C-MAG HS 7 control Betriebsanleitung

/// Controlling the medium temperature limit
using a contact thermometer
The preferable method for controlling the average temperature is with
contact thermometer. After the set point temperature has been adjusted,
this results in a short heating-up time, practically no temperature drift and
only minor fluctuation in temperature.
A 6-pin jack is located on the rear side of the device for connecting the
PT 1000 series, contact thermometer or the contact plug. The electronics of
the devices returns a test current that must flow via connector pins 3 and 5
for the heating plate to heat up.
Safety contact thermometers
Acc. to DIN 12 878 class 2 or acc. Gerstel are connected with a three-wire
cable, the test current flows through the contact thermometer.
Safety function
If the test current is interrupted because of e.g. breakage of contact thermo-
meter or falling out of the cable plug, the heating cuts off.
Contact thermometer without safety circuit
Acc. to DIN 12 878 class 0. The device only heats if the test current circuit is
closed by an electrical connection of the plug pins 3 and 5.
2-wire connecting cables
Connect plug pins 3 and 5 of the device plug.
3-wire connecting cables
Here the test current circuit can also be produced in the terminal
head of the contact thermometer (connect plug pins 2 and 3).
A 3-wire cable with the required bridge is available (accessories).
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Settings
For detailed instructions for settings and limit values, please refer to the
operating manual of the instrument you are connecting.
The desired average temperature can be adjusted on the contact
thermometer. The required surface temperature of the heating
plate can be selected with the rotating knob (temperature) or
button.
Adjusting the temperature of device to the maximum adjustable tempera-
ture will result in the fastest possible heating time, but the average tem-
perature may fluctuate to values above the set-point temperature on the
contact thermometer. By adjusting the rotating knob (temperature) or
button to approximately twice the set-point value of contact thermometer
(with a set-point of + 60 °C, the temperature of device would be set to
+ 120 °C), you will reach a good compromise between a fast heating
time and over-shooting the set point. If you adjust the temperature of the
device to exactly the set-point temperature, the medium will not reach
the set-point temperature because some loss of the heat will always
occur between the heating plate and the medium.
If a fault occurs in the control circuit, the maximum heating
plate temperature can be adjusted with the safety temperature
setting screw.
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