HMI and VisualPlant, a Manufacturing Intelligence

With only a cursory glance at VisualPlant, it would appear as though it overlaps significantly with an HMI system. The objective of this document is to examine both systems to define where and how they overlap.

In general terms, HMI systems were designed as client-server applications to layer on top of a smaller number of PLCs. They are optimized to visualize, control, and report on data that is either being polled from or sent from PLCs in near-real-time. The extent of historical data available from an off-the-shelf HMI is usually limited to an event/incident log as well as process variables that are utilized in a trending environment. Extensive customization is required to create a contextual, historical database, effectively resulting in a custom solution for the customer. HMI solutions are Level 1 data acquisition systems.

In general terms, VisualPlant was designed as an off-the-shelf, N-tiered system to connect to any number of PLCs/machines/assets (practically speaking, up to 4000 PLCs), bring relevant data into one database (MS SQL) and provide a visualization, analysis, and reporting framework in a web browser. An essential point is that as an off-the-shelf solution, this is accomplished without writing a single line of code, and without ever creating or editing a database. VisualPlant is designed as a Level 2, non-intrusive, mission-critical data collection application, not for control.

The following diagram and accompanying comparisons, while not exhaustive, show conclusively that both applications play a clear and distinct role in plant floor operations -- with minimal overlap.

Generic HMI & VisualPlant Feature Comparison

Off-the-shelf HMI

• Point of control: Yes


• High level graphical capabilities: Yes


• Graphical animation: Yes


• Alarm/Fault management: Yes


• One database for entire plant: No


• Historical database (out of the box): No


• Web browser exclusive client: No


• N-Tiered architecture (contemporary MS.NET architecture): No, client/server


• Licensing strategy: By tag count & client users


• Uses standard open database: No


• BizTalk interface to 3rd party software: No


• Typical # of PLCs interfaced to: 1-10


• Typical # of web clients: 1-30


• Data mining tools: No


• Extensive built-in reports: No


• Extensive real-time & historical analysis tools: No


• Adding data points/machines/lines without shutting down: No


• Unique profiles/graphical dashboard/perspective for each user: No


• Designed to be on the plant floor: Yes

Off-the-shelf VisualPlant

• Point of control: No


• High level graphical capabilities: Some


• Graphical animation: No


• Alarm/Fault management: visibility but not management


• One database for entire plant: Yes


• Historical database (out of the box): Yes


• Web browser exclusive client: Yes


• N-Tiered architecture (contemporary MS.NET architecture): Yes


• Licensing strategy: By asset/machine (unlimited users)


• Uses standard open database: Yes


• BizTalk interface to 3rd party software: Yes


• Typical # of PLCs interfaced to: 10-4000


• Typical # of web clients: Unlimited (500)


• Data mining tools: Yes


• Extensive built-in reports: Yes


• Extensive real-time & historical analysis tools: Yes


• Adding data points/machines/lines without shutting down: Yes


• Unique profiles/graphical dashboard/perspective for each user: Yes


• Designed to be on the plant floor: No

Conclusions

The most obvious overlap is in the area of visualization -- both software applications include the capability for real-time data visualization. The other significant possibility of overlap is in the extended functionality of an HMI system by means of custom development. However, more extensive research and investigation will clearly show that not only is there minimal design overlap, there could be significant collaboration between an HMI platform and a Manufacturing Intelligence platform.

AMRResearch positions HMI systems (Level 1 Supervisory Control and Data Acquisition systems) in a space of their own, and VisualPlant in a newly defined space identified as Enterprise Manufacturing Intelligence (EMI), a Level 2 system. Please refer to the AMRResearch Outlook for a clear definition of EMI.