When we talk about temperature controllers, they are basically of three different types, namely on-off, proportional controls and PID. Depending on the system that is to be controlled, the user may use any one type of the three controller to control the process. On-off controllers are the simplest form of controls as they virtually require no set up. In them, the turn-on and turn-off temperatures differ by a very small margin. This prevents rapid switching of the machine, when the temperature is about to reach the set-point. PID controls are an improved version of proportional control and they come with an integral and derivative function. This checks initial overshoot and also eliminates temperature instability, once the set-point is achieved. They allow the temperature process to be reached quickly without any overshoot or continual fluctuations (temperature errors). PID controllers come with an auto-tune feature, which automatically controls the process of thermal dynamics. In them, only the energy required to reach and maintain the temperature process is used, hence preventing any wastage of energy.
Out of the three, PID controllers are the most accurate and stable controls and they are best suited for systems which have relatively small mass. They are preferred in systems where the load changes more often and the controller has to adjust automatically due to frequent changes in set the point. Besides this, there are multi-loop controllers in which, each control loop consists of at least one input and one output. There are numerous multi-loop controllers that can be purchased online and they can easily handle more than one control loop. Some can even handle as many as seven control loops. Nowadays, safety limit controllers are also available in the market. They are basically off-off controllers with a latching output. In them, whenever there is a change in the state of the output, a manual reset is required to change it back to the original. They are mostly used to shut down a process when unwanted temperature limits are reached.
Eurotherm 2208e
These days, 2208e series of Eurotherm temperature controllers / programmer can be easily purchased online and at a price much less than that in the market. The programmers of this series are known for their versatility and high stability. They have a modular hardware with separate heating and cooling outputs. They give customized operator display which is very beneficial in digital communications. They also provide self-tuning with overshoot inhibition. Eurotherm 2408 controllers are also known to provide self-tuning with overshoot inhibition.
Out of the three, PID controllers are the most accurate and stable controls and they are best suited for systems which have relatively small mass. They are preferred in systems where the load changes more often and the controller has to adjust automatically due to frequent changes in set the point. Besides this, there are multi-loop controllers in which, each control loop consists of at least one input and one output. There are numerous multi-loop controllers that can be purchased online and they can easily handle more than one control loop. Some can even handle as many as seven control loops. Nowadays, safety limit controllers are also available in the market. They are basically off-off controllers with a latching output. In them, whenever there is a change in the state of the output, a manual reset is required to change it back to the original. They are mostly used to shut down a process when unwanted temperature limits are reached.
Eurotherm 2208e
These days, 2208e series of Eurotherm temperature controllers / programmer can be easily purchased online and at a price much less than that in the market. The programmers of this series are known for their versatility and high stability. They have a modular hardware with separate heating and cooling outputs. They give customized operator display which is very beneficial in digital communications. They also provide self-tuning with overshoot inhibition. Eurotherm 2408 controllers are also known to provide self-tuning with overshoot inhibition.
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