HMI Mobility: Remote Access, Any Time, Any PlaceDownload Now
The benefits of remote access for manufacturing operations are widely known and accepted. This article details how modern SCADA systems are providing this access in a variety of ways to all manner of fixed and portable computing platforms and other devices.
Simple HMI systems have evolved into highly advanced SCADA solutions that provide key data to operators, engineers and plant managers from any location.
Human Machine Interface (HMI) has evolved significantly from the days in which operations staff had to sit in front of a single screen to monitor a machine or a process. HMI /SCADA (Supervisory Control and Data Acquisition) applications now not only monitor and help control equipment and processes, but also provide a huge range of information regarding machine and plant operations. Since many people consider HMI to be a low-end panel-mounted apparatus, the term SCADA will be used to refer to the more advanced applications discussed in this article.
Table 1 lists the various ways in which HMI and SCADA systems provide remote access to users. At the most basic, a panel-mounted HMI with built-in web server capabilities provides some limited degree of remote access via a web browser. This access is often only one-way, allowing remote users to view information, but not to make changes.
The next step up is again server-browser access, but this time via local SCADA software, generally running on a PC installed locally at the machine or the process. Although the remote access is still via browser, in most cases this access is more full-featured than with a simple HMI, allowing remote users to view more information in a wider variety of formats. SCADA server-browser access also usually provides two-way access, allowing for remote adjustments and corrections