Technical Blog

3 Unconventional Uses for HMI

This blog post sets out to look at a few unconventional uses for HMI that you might not yet be aware of.

Most machine builders are familiar with modern touch screen HMI's that have all but replaced older style toggle switch panels.  It has enabled machine builders to give operators much more information on the process going on in a machine.  HMI's can look at a multitude of machine variables and they can be presented in a more relatable graphical format than digital readout or analogue meters. 

For instance, instead of a tank volume number, you can visually show the operator how much fluid is in the tank.  HMI's however can go even beyond these operator related touch-screen graphics.  Some of the more sophisticated features can really benefit machine builders and end-users. 

Unconventional Use #1 - Alarms 

The first unconventional use for an HMI involves monitoring Alarms. Alarms are not just about warnings, although it is a common usage to alert an operator of a certain condition.  The HMI program is set to monitor a variable in the controller and when the condition is met it could force an action from the operator, or even send an email to a supervisor. 

HMI's can even sequence machine functionality without operator intervention acting like an automated machine controller.  This is non-traditional, but clever when an HMI is used to sequence two machine modules together using alarms. 

It is especially helpful when older machines are linked together to form a line, but augmenting the machine controllers is not possible because of lack of source code or complexity of programming.  Alarms are simple conditional statements that trigger actions or alerts, and are just one of the unconventional uses for HMI.   

Unconventional Use #2 -Schedulers 

Another unconventional use for HMI is a Scheduler; a time-based occurrence that is completed by the 

HMI.  It is similar to an alarm but it is time based using the HMI's real time clock.  Schedulers can be used to validate that operators perform a diagnostics check of the machine.  For example, this could be when scheduling a door interlock switch check and making sure that it changes state during a given shift.  Failure of the operator to check the switch leads to a lockout of the machine at the next cycle stop and requires a supervisor to enter the passcode.

Unconventional Use #3 - Data Logger/Trending 

The third unconventional use for an HMI involves Data logging which can be stored locally on an SD card or exported out HMI using the Ethernet port.  Data is logged in an industry standard SQL format and can also be exported to Excel using included database tools.  Data logging can even be used in the development of the machine by the OEM.  For instance the HMI can become the tool to gather lifecycle test data or a tool for debugging.  Any machine variable can be passed from the controller to the HMI for recording. 

A benefit of using the HMI for this purpose is less risk to the main machine controller.  Often the process of collecting data can add complexity to the machine code.  Passing data to the HMI gives a division of labour in order to validate the main machine controller without introducing unnecessary code.  Trending is an extension of Data Logging that includes the visualisation of logged data for display onto the HMI. 

Trends of interest might include graphing machine run time vs. idle time or looking at product upper and lower control limits over time.  This is a benefit to the end-user of a machine.  Trending is a free tool that an OEM can use to show end-users how to analyse their own effectiveness, and another of the unconventional uses for HMI.

These examples are just three of the unconventional uses for HMI. Take a look at our HMI Controller product page to see how we can help you to benefit from deploying these Controllers on your machinery.

This article was originally authored by Reid Hunt of Kollmorgen, and reposted by 

Heason Technology with the kind permission of Kollmorgen. Heason Technology is the Gold Distribution Partner and Systems integrator for Kollmorgen in the UK. 

For further information, contact sales@heason.com or call us on +44 (0) 1403 792 300. 

 

 

Article published on: 26/11/2015