Overview

Process control and monitoring systems cover applications as diverse from biscuit baking to power stations to building management HVAC systems.  Commonly used devices for control are Programmable Logic Controllers (PLC) as these can input and output electrical signals.  For example a PLC might switch on and off a heater to keep a temperature constant. PLC systems vary in size from the smallest have just a few inputs and outputs (I/O) to systems having 1000’s of I/O.  PLCs typically have internal programmed logic such that they can independently exercise the control of the process.   However they are often connected to a higher level system that is used to set process condition targets and to monitor the overall process.

The higher level software is usually termed SCADA – supervisory control and data acquisition.  There are many SCADA packages available on the market and because this is a long standing requirement most have a long history dating back to the 80’s.  As the development of SCADA has progressed most packages try to encompass all features and devices ever needed.  Also because of the installed base packages are constrained by backwards compatibility and upgrade paths.  This means that most packages are complex to learn, heavyweight installation and based on a very high cost per I/O point and per PC license.  Usually there are two licenses to buy: a license to develop a system and a second license to run a system.  This is easily demonstrated by reviewing SCADA suppliers web sites and reviewing the number of training courses and where available the charging model.

Enter Whzan.  It was designed to be a tool for displaying, monitoring and controlling data for many different processes.  It is Internet Cloud based, scalable, accessible and links to many common PLCs. Download the Whzan gateway software to communicate with your PLCs and use the Internet based editor to create process graphics (mimics) to show the data in near real time.  There is no license to purchase and because of the simplicity most find it intuitive to use so there is no need for training courses.

• Easy to use
• Cost effective
• Expandable
• Remotely viewable
• Has a wide range of supported devices

Although Whzan doesn’t have all the features found in the biggest SCADA packages, it does have:

• updating interactive process graphics
• history and graphing
• alarms with alerts to email and twitter.