Hi my name is Dominick Deluca I am the president of New England Temperature Solutions. Today's topic is on how to select a controller. We will talk about size, cost Versus function, inputs, output types, control types, alarm types, Digital Communications, Ramp soak, and other options.
Size: There are four basic sizes all based around a unit of measure called a din. In the temperature control market most controllers come in four sizes;
Quarter Din measuring 96 x 96 mm
Eighth Din measuring 48 x 96 mm
16th Din measuring 48 x 48 mm
32nd Din measuring 48 x 24 mm
All of Eurotherm's temperature controllers have the same basic functionality regardless of the size, however the limitation becomes inputs and outputs. For instance, the basic 32nd din controller only has terminals for one input; power, and two outputs, while a fully loaded ¼ din controller such as a 2704, has enough terminals for two inputs and up to 10 Multiple combinations of inputs and outputs. The bigger the controller, the more I/O, the more features, and the higher the price.
Selecting the proper controller size will be determined by the 4 things.
First, the amount of I/O needed. I/o needed will be determined by the process.
2nd, the size of buttons needed. If your process requires you to wear gloves chances are the 32nd din controller will not work, that is unless you decide to prematurely destroy it by changing the setpoints with the pen.
3rd, the size of the display. How far away do you need to read the display from and what resolution do you need. Small controllers only have so many digits if you are looking for 1200.0° resolution need to buy a larger controller.
4th, Existing Installation: If panel space is not an issue and you are replacing a ¼ din or larger controller, you may want to buy a bigger controller. If you don’t, we sell adapter plates for between 30 and $50 to cover larger holes. If you need to build the panel you may want to opt for the small controller to save on panel space.