Understanding Temperature Controllers And Its Three Basic Types: 2408 Eurotherm

Posted by michaelalbert on July 6th, 2017

In order to control the process temperature accurately without a constant operator involvement, almost all industrial thermal process relies on the performance of a controller.

As the name implies, a temperature controller is an electrical equipment designed to control temperatures that doesn’t involves an external operator of any kind. This temperature control system receives input from temperature sensors such as RTD, or thermocouple, compares the actual temperature to the desired control temperature (preferably a setpoint). in the end, the controllers transmits a electrical signal, which can either be voltage or current to a power switch instrument (such as solid, state relay, simple relay, or silicone controlled rectifier).

Temperature Controllers: Its Types

Basically, temperature controllers can be divided into 3 subdivisions, namely - on-off, proportional, PID. An operator chooses a type, depending upon what kind of system is required to be controlled.

Let us understand all three in great detail.

On- Off Control:

Being the simplest form of temperature controller, the output acquires only two states, “On or “OFF”. there is no middle state here. This control system turns the power ON or OFF only when the setpoint is crossed. Such systems are ideal when process temperature is not critical or larger masses are required to be heated , say for example immersion tanks. In addition, it is employed where a precise control is not necessary, in systems which cannot handle having the energy turned on and off frequently, or for a temperature alarm. Controller uses a latching relay that can be used to reset manually, or even shutting the entire process once a certain temperature is reached.

Proportional Controller:

the cycling which was an inherent problem in the On -OFF controllers has been eliminated in proportional control. As the temperatures reaches setpoint, It decreases the average power delivered to the heater. As a result of this, it doesn’t overshoots the setpoint, but will approach the setpoint and maintain a stable temperature.

Microprocessor Control (aka PID control):

Microprocessor control involves a control feedback mechanism excessively utilized in thermal control systems. Such controllers corrects the error between an evaluated process temperature element and the expected temperature (setpoint), followed by a corrective action that adjusts the process accordingly.

After reading this article , you must have gotten aware of temperature controllers and its basic types. 2408 Eurotherm is a widely used temperature or process controller ideal for glass furnaces, kilns, Pharmaceutical applications etc.

Author’ bio: Author is an avid online blogger. The article is on 2408 Eurotherm Temperature Controllers.