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Accelerating the path to discovery
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It is imperative to NOTE that the Setpoint Controller, or the meter at the top, is the only object of the discussion
in Section 2. The reaction’s heating is controlled by the setpoint controller. The temperature management of the
reaction is unaected by the High Limit Controller (i.e., the meter on the bottom), which only responds to over-
temperature conditions. As shown below, just the setpoint controller must be adjusted.
The controller’s most potent function is its capacity to control nearly any heating mantle with a constant
temperature. For steady regulation, the controller must be tuned to the heating mantle being used.
The process of tuning involves balancing the heating mantle’s heating properties with the controller’s control
characteristics. When the controller’s memory is set up with information on the heating mantle’s rate of warming
up, rate of cooling o, and eciency of heat transfer, the heating mantle is said to be tuned to the controller. Think
about the distinctions between a hot plate and a lament bulb, for instance. A lament bulb instantly starts to heat
up when power is supplied, producing both light and heat. Additionally, it instantly shuts o when the electricity is
cut o. A hot plate, on the other hand, could take a while to start heating once power is applied and considerably
longer to stop heating after electricity is turned o. A hot plate and a heat light may be controlled by your controller
to 0.1 degrees Celsius. To achieve this, however, it must be programmed with the time constants that indicate how
quickly the heater heats up when the power is switched on and how quickly it starts to cool down when the power is
turned o. The tuning parameters are the names given to these time constants.
Tuning parameters vary depending on the type of heating mantle. The tuning parameters for the heating mantle
that is currently in use must be programmed into the controller for it to heat steadily. Since heating mantles are the
most frequently used heaters in research, tuning settings that enhance heating performance for these heaters were
put into the controller before shipment. Five of the temperature meter’s user-programmable functions are used to
control tuning. The user can manually calculate and load the proper value for these 5 functions, or the controller
can do it for them using its autotune functionality.
When Should the Controller be Tuned?
Any size heating mantle can be utilized without having to retune the controller if it has been tuned for a certain
type of heating mantle. When switching from heating mantles to another form of heater, the controller should be
calibrated with values that describe the oven heater’s heating properties. Below, the result of adjustments is visible
in the plots illustrated. When the controller is adjusted for heating mantles, using it with a heating mantle of any
size results in reliable temperature control (Plot 1). However, when the same tuning parameters are employed with
another heater, poor control is the outcome (Plot 2, Curve 1). Reliable temperature control is only achieved when
the controller is adjusted for the heater (Plot 2, Curve 2).
NOTE: Before your controller leaves the factory, Ecodyst Scientic, Inc. makes sure it is already tuned to t
the specications of the heating mantle you ordered. As a result, your controller doesn’t require any more
adjustment. Contact us for assistance and technical guidance before making any technical modications if it
does need to be tuned because of a change in the heating mantle.
2.1 Tuning
2. Adjusting the Controller for Stable Control With Different Heaters
High Powered Heating Mantle Controllers
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