“There is no such thing as information overload.
There is only bad design.“
In this series of articles I will be describing some tips and guidelines on how to design human-machine interfaces (HMIs) in order to obtain improvements in the results of the process operation. The concepts apply to any SCADA system in any type of industry, but I will sometimes be particularizing for the case of the electrical sector.
The concepts presented here are based on the research and recommendations on User-Centered Interfaces in SCADA systems made by the ASM Consortium in the book “The High Performance HMI Handbook” by Hollifield et al. (ISBN-10: 0977896919), in the guidelines of the ANSI / ISA101.01-2015 standard (Human-Machine Interfaces for Process Automation Systems), in my investigation of the fundamentals of the interface area and in the practical experience of adapting this methodology to the remote control operation of Power Transmission Substations.
What you and your company can gain from this? According to a scientific test developed by the ASM Consortium, a User-Centered Interface compared to a traditional interface achieved the following results:
- Problems were detected by the operators 5 times more, before the first alarm.
- 36% Gain in success rate in completing the proposed operations.
- Operators completed tasks 41% faster.
These are extraordinary gains that translate directly into financial benefits, safety and quality of operation, please note that these are obtainable only through the reconfiguration of the HMI, there are no other investments.
Of course the results can vary greatly from case to case, but the benefits are quite obvious once conceived, implemented, tested and put into practice the new interface. In the practical case that I implanted, the new interface obtained an index of more than 80% of approval from the operators, which is extremely significant for the environment of the electric sector where the resistance to the change is notorious.
The importance of the subject is such and the results so concrete that it has motivated the creation of the ISA101 standard. The standard sets out recommendations and best practices that cover the entire lifecycle of the HMIs. The ISA101 standard aims to:
- Provide guidance on the design, implementation, operation and proper maintenance of HMIs that result in the safest, most effective and most efficient process control under all operating conditions.
- Improve the operator’s ability to detect, diagnose and respond appropriately to abnormal situations.
According to ISA101, Situational Awareness is classified into three levels:
- Level 1 – Be aware of what is happening in the process.
- Level 2 – Understand the current state of the process.
- Level 3 – Understand what should be the probable state of the process in the future.
One of the fundamental characteristics of User-Centered Interfaces is to empower the operator to precisely understand the present situation and to be in a good position to predict the state of the process in the near future and, thus, to have a more preventive action on the process and no longer simply respond to alarms. This is only possible by providing information, in the form of suitable visualizations, in context to the operators, when they need it, and not simply reproducing on the screen the P & ID or single-line diagrams with scattered numbers representing process measurements (traditional methodology allows to reach only Level 1 of Situational Awareness).
With this introduction, I hope to have motivated the professionals who, in some way, participate in the process of operation and conception of the HMIs to pay more attention to them, since the opportunity to obtain significant gains through the understanding and application of the concepts that will be presented in this series of articles.
#SCADA #HMI #IHM #interface # ISA101 # operation # substation