IKA color squid white 0003671000 [32/35] Temperature regulation

Knowledge

/// Temperature regulation

Excellent temperature control is a critical factor in heating operations

to eectively address rheological changes in samples. The ETS-D5

can be attached to all IKA magnetic stirring and heating devices with

DIN bushing 12878 class 2, and also from other providers.

The ETS-D5 is an electronic contact thermometer with 3 operating

modes. The electronic thermometer with optimized PID control ensures

perfect temperature control without overshooting the set temperature,

even in the case of quick heating.

PID control

PID stands for Proportional-Integral-Derivative, referring to the three

terms operating on the error signal to produce a control signal. Some

applications may require using only one or two actions to provide the

appropriate system control. P (Proportional) control can provide a stable

process temperature but there will always be a deviation between the

required set point and the actual process temperature. I (Integral)

control represent the steady state error of the system and will remove

set point / measured value errors. For many applications, P + I control will

be satisfactory with good stability and at the desired set point. D control

is usually used for processes with rapidly changing process outputs.

For example, if you heated up a liquid to a certain set temperature, the

liquid no longer gets heated up. If the liquid cools down slowly, the PI

control reacts immediately and slightly heats up the liquid. So it appears

as though the liquid can hold this temperature without any deviation.

In reality, the controller responds to the slightest temperature ﬂuctuations.

If you add ice water to this liquid, the temperature changes very quickly.

The D control responds to the rapid changes until the desired tempera-

ture is reached. Then, the dierence of the temperature to be achieved

is not too big and the last ﬁne tuning is controlled by the PI control.

By tuning P, I and D, a very fast and accurate temperature control can

be achieved!

20 40 60 80 100 120 140 160

COMPARISON: PI, 2-POINT AND PID CONTROL

(TARGET TEMPERATURE 50

2P-Control PI-Control PID-Control

Temperature in

62 63

Magnetic Stirrers Magnetic Stirrers