Temperature and process controllers are generally divided into one or two categories: single-loop and multi-loop.
When should I use a multi-loop controller?
If you have more than one control loop in a single system, then you can use a multi-loop controller. In simple terms, it can be considered that a multi-loop controller can contain multiple temperature controllers in a single instrument.
Typical use and benefits
Multi-loop controllers are usually mounted at the back of the panel, unlike single-loop controllers that are often mounted in the front. Controllers are usually programmed using a proprietary software program on a PC that downloads the settings to the multi-loop temperature controller using communication.
Using a multi-loop controller rather than multiple single-loop controllers can have many benefits. Installation costs can be reduced due to the common connection point, which limits the number of cables and reduces panel cuts. Another advantage is that the controllers can be changed without stopping the system. This process, known as hot swapping, significantly reduces the downtime of the machine.