EMS Electrical Services: Your Experts in PLC and HMI Technologies
Here at EMS Electrical Services, we offer a comprehensive range of PLC and HMI services to commercial and industrial operations in Auckland and surrounding areas. We are experts in this technology.
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PLC stands for Programmable Logic Controller and plays an integral role when it comes to SCADA and HMI systems.

Trust EMS Electrical Services to take care of all your PLC programming, control cabinet design and information technology needs in Auckland. We are the experts to call for automated industrial and commercial lines. We develop innovative solutions when it comes to information technology, production and systems control.

How Do PLCs Work?

PLCs are actually more simple than you may think. They work on a cycle of four key stages.

Through input scans, PLCs are able to detect the state of all their input devices. From there, a program scan takes place, in which the program connected to the PLC is scanned. The next scan is the output scan, in which all connected output devices are scanned. The last step of the cycle is referred to as ‘housekeeping’ which ends the loop and essentially performs a general check on everything.

How Are PLCs Programmed?

Most modern PLC systems will give you the option to program in Ladder Logic. Ladder Logic is a commonly used programming language that allows you to customise your PLC’s programming to suit your specific needs. The left side usually consists of input contacts, while the right side is made up of output contacts. Programming is fairly simple and adjustable when necessary.


In addition to our PLC services, EMS Electrical Services also specialises in HMI technologies. HMI is a local machine used to communicate with PLCs to bring the whole system together. HMIs are screens that allow for the easy operation of PLCs and systems, providing convenient visualisation of certain processes and programming. Our team can install and program these devices.

Connect With Us to Discuss Your Next Project

Speak to our experts in industrial automation in Auckland today about your upcoming project.