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The unit has a built-in 600 W heating plate with a stainless steel or
coated surface (C). Heating is controlled by a wear-proof, electro-
nic TRIAC element.
The heating plate is kept at a constant temperature by a control cir-
cuit. The heating plate temperature can also be monitored from a
separate, adjustable safety circuit. The two temperature sensors
(PT 1000) for this purpose are built into the heating plate.
The heating plate safety circuit (SAFE H (hotplate)) can be set in
the temperature range from 50° to 350 °C.
The unit can also be controlled from a single, external PT 100 tem-
perature sensor or from twin PT 1000 temperature sensors.
Any external temperature sensors must be plugged in before the
unit is switched on so that the automatic self-test/sensor recogni-
tion cycle can take place.
The external temperature sensors (medium) are monitored by a
separate, adjustable safety circuit. The medium safety circuit
(SAFE P (probe)) can be set from 50 to 350 °C or to the maximum
setting of the heating plate safety circuit.
Use the ”Temp” knob to set the setpoint temperature required in
the range from 0° to 340 °C (max.) The temperature set will be dis-
played on the upper right-hand side of the digital display. ”SV” and
”PROBE” will flash.
To switch the heating function on and off, use the ”Temp” mem-
brane button.
When the heating function is switched on, the green ”Temp” will
light up and the digital display will switch to the next display page.
The actual temperature is displayed.
While the plate is heating up, the green ”Temp” LED will change
colour from green to orange (orange = power supply to heating
plate).
11.1
Control of medium temperature with
PT 100 temperature sensor
When the unit is switched on, the message
”PT2 OFF” is displayed.
The ”PROBE” symbol is shown on the digi-
tal display to indicate that the PT 100 sensor
is operating. The setpoint and actual tempe-
ratures displayed are for the medium.
The heating plate temperature is limited by
the setting of the safety temperature circuit
(SAFE H).
The medium temperature is controlled and
regulated by a fuzzy logic controller. This
ensures that the medium, sensed by the
PT 100 sensor, is heated as quickly as pos-
sible without exceeding to the set tempera-
ture. The fuzzy logic controller automatically
adjusts to the various heating capacities of
different vessels and their content. This sys-
tem ensures optimum temperature control
without temperature drift or fluctuations.
11.2
Medium temperature control with twin
PT 1000 temperature sensors
When the unit is switched on, the message ”PT2 OFF” is dis-
played.
The ”PROBE” symbol is shown on the digital display to indicate
that two PT 1000 sensors are operating.
Heat transfer medium and reaction medium (2 vessels)
There is a temperature sensor in the heat transfer medium and a
temperature sensor in the reaction medium.
Automatic recognition of the heat transfer and reaction medium
sensors takes place.
Function heating
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