Labnet AccuPlate Hotplates, Stirrers and Hotplate Stirrers - Manual (Page 7)

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 Constant Display: The number shown on the Heating Temperature Display will
remain constantly ON when the actual heating temperature is at the set
temperature.
 Hot Top Indicator: The Hot Top Indicator will be ON at all times when the
temperature of the top surface is too hot to touch (greater than ~60°C).
 The Hot Top Indicator will FLASH when the Heat Control Knob is turned OFF
but the top surface is still too hot to touch.
 The Hot Top Indicator will be OFF when the temperature of the top is less than
~60°C.
Heating Operation Principles
The heating element and a temperature sensor are located just beneath the ceramic top surface
of the product. The microprocessor controlled heat, generated by the heating element, is based
upon the sensor temperature and the value set on the Heating Temperature Display. When the
sensor temperature is not within range of the value set on the display, the display will FLASH.
When the sensor temperature is within range, the value displayed will remain constantly ON.
The Heating Temperature Display does not indicate the actual temperature of materials placed on
top of the product or the actual temperature of the ceramic top surface.
The table below shows a typical difference between the temperature set on the Heating
Temperature Display and the actual temperature measurement of the ceramic top surface:
Temperature Set
on Display (°C)
Actual Top Surface
Temperature (°C) Temperature Set
on Display (°C)
Actual Top Surface
Temperature (°C)
50 45 350 285
100 85 400 325
150 125 450 365
200 165 500 405
250 205 550 440
300 245
(The information above was taken using a D0420 with no top load in 20°C ambient conditions)
Using the External Temperature Controller enables precision temperature control of materials placed in vessels on top
of the product.
An External Temperature Controller is available for this product as an accessory item. Contact
your Labnet distributor for additional details.
When the External Temperature Controller is connected to the product, the closed loop control
process described previously is extended to include temperature input from the External
Temperature Controller. The microprocessor controlled heat, generated by the heating element,
is based upon the sensor temperature located in the tip of the External Temperature Controller
and the value set on the Heating Temperature Display. When the sensor temperature is not
within range of the value set on the display, the display will FLASH. When the sensor
temperature is within range, the value displayed will remain constantly ON.
When the External Temperature Controller is connected to the product and properly placed into a
liquid on the top surface, then the Heating Temperature Display does indicate and directly control
the actual temperature of the liquid on the top surface.
Caution: The top surface and the vessel used may be at substantially higher
temperatures than indicated by the setting on the Heating Temperature Display as
the controller regulates the liquid temperature inside the vessel.