Fit for purpose is a mantra that permeates many areas of industry, but it is in engineering and process control – especially in terms of value and ease of use – that it is clearly evident. ‘Best-fit’ solutions arguably deliver optimum value, not just in terms of procurement costs, but also lifetime costs and functionality.

 

One discipline in which it is tempting to over specify is temperature control. Therefore, in order to reach an effective conclusion in the specification of temperature controllers, it is important to understand their core features and functionality and decide what you do and do not need; then use this information to make a more informed choice.

 

Most industrial and process applications are not classed as critical from a temperature perspective. Sensor input accuracy to low fractions of a percent is available, but the more accurate you go the higher the cost. Users can also be presented with a range of I/O options, many of which may never be used. These features may sound attractive, but if they are not being leveraged by the application, they are simply surplus to requirements.

 

Unnecessary in-controller features come at a cost and add complexity, making set-up times longer. These added features also demand commensurate additional processing power, which again equates to more cost. Extra complexity also means that there is the potential for more to go wrong.

 

The user interface is another major consideration. If you only want to see the temperature and setpoint, you must ask the question: why pay for the ability to see more information, when the chances are that you will never need to use it? More complex displays are often also oriented towards the person configuring controller rather than the end user, so the user ends up paying for something they don’t actually need. The same is true for user menus. Long menus take longer to programme and have settings with which users may not be familiar. The argument here is for shorter, more concise menus that deliver just the core parameters and features.

 

Plant managers and OEMs need to ask themselves what the controller is being used for, what accuracy levels are required, which core parameters need initial and regular access, how many I/O are they likely to use regularly and what functionality is needed in terms of profiling, control and feedback. By answering these questions the concept of fit for purpose comes to the fore and makes the selection far simpler and, arguably, more cost effective, not just in terms of initial purchase, but also in terms of overall cost of ownership.

 

A case in point is the new MAXVU compact controller from West Control Solutions. Designed using significant user and customer input, this controller covers a vast range of applications and when combined with its easy set up, it exemplifies the best-fit concept. It has been specifically designed to offer extremely fast set up (as quick as 60 seconds) in less-demanding temperature control applications thanks to its start-up configuration applying settings to only the most vital parameters. Should additional functionality be required, users have access to a wider parameter set, but these are not displayed in the default quick-start menu.

Ring-fenced parameters and simplified visuals do not mean that the MAXVU is any less capable. Indeed it offers many outstanding features such as a bright and unambiguous display which, I believe, offers the largest display digits of any 1/16 DIN (48 x 48mm) controller. The display, which shows current temperature and the desired temperature, is also legible from longer distances and wider viewing angles, giving additional installation flexibility.

In summary, selecting more features just for the sake of future proofing is an ineffective, unaffordable and unsustainable business decision. Driven by market demand, best fit solutions are now considered by far the most sensible option.