13.5 Arc flash evaluation.

Virtually all software is capable of running IEEE 1584 studies, but this will need checking that the studies are to the latest standard. There are few software companies that have the capability of running the box test arc flash evaluation calculations, but some companies have developments of the standard. This is the German standard DGUV-I 203-078 for arc flash hazard calculations and is recognised in several European countries as well as IEEE 1584-2018. This will allow the user to choose between arc protection class 1 or 2 personal protective equipment in accordance with IEC 61482-1-2 (Box Test) and is described in more detail in Chapter 7: Protection.

13.6 Number of buses.

The cost of software is often determined by the number of buses that are required. To purchase software on the number of circuits in a facility is likely to be extremely prohibitive and it is suggested that exclusions of smaller circuits are made for art flash evaluation. If it is considered that every circuit will have to be modelled, then a possible solution may be to breakdown the electrical system into smaller networks and use software with a lower number of buses. It will be prudent to check the cost of upgrading to a higher number of buses as the initial purchase may have been for a bundled offer. There is, therefore, a chance that upgrades may be quite expensive when compared with an up-front cost.

13.7 What else do you need to use the software for?

What other features may be required of the software? If you need to use the software for the evaluation of system disturbances, harmonics motor starting etc it will be good to establish those requirements at this stage. It may be that the software is not capable of undertaking such studies which may mean that such an oversight could be a costly mistake not only in terms of software but also time.

13.8 Labels

Where North American software is proposed, some care is required in selecting the correct labelling formats. As discussed in Chapter 6: Process, Policies and Procedures, the European approach for labelling is less prescriptive than in the USA/Canada but there is a general requirement that employers must provide safety signs where there is residual risk. Warning signs must be standardized across Europe in a way which will minimize the potential problem that may arise from linguistic and cultural differences between workers. U.S style labels based on ANSI Z535 are not acceptable in Europe as the colours and symbols do not conform to the European legislation. The software must be capable of designing European style labels and the language is another consideration. Warning signs for instance, must be yellow (or amber), they must be triangular and the yellow must take up at least 50% of the sign. Information from arc flash studies can be included such as the incident energy level, PPE and various approach boundaries. The table in Chapter 6: Process, Policies and Procedures gives the meaning of each colour.

13.9 Technical Support

The user experience with any computer software is dependent upon the quality and availability of the Technical Support. This is very important when it comes to electrical engineering software support. I know engineers who have chosen to use slightly inferior or more expensive software but where they have a good relationship with the software support technicians. Whilst that relationship might be difficult to measure in the early stages, questions that could give some key performance indicators will be speed of response. So, questions like “how long will it take for a missing protective device to be modelled into the software” may help. Good software companies are proud of their customer facing engineers and their qualifications and experience are usually displayed on their websites, papers and/or training webinars.

13.10 North American Electrical Safety Standards

The Standard for Electrical Safety in the Workplace, NFPA 70E in the USA mandates the use of an Energized Electrical Work Permit. As a result, North American software companies sometimes embed an energised permit printing facility. As detailed in Chapter 6: Process, Policies and Procedures, be careful, as the use of an energized electrical work permit would not be acceptable in the UK as electrical permits are restricted to dead working only.

13.11 Cost

Electrical design and modelling software services is a competitive market, and it is worth shopping around for bundled offers which, will sometimes, present good value for money. Software companies also offer leasing facilities and it is worth the time and effort in order to compare costs over time of software procurement. For instance, there is the option of a perpetual licence but the cost over time will have to take into account the annual support package. Once an allowance has been made for inflation a more attractive proposition may be to lease to software.

The way in which software is packaged varies substantially between manufacturers. This makes it more difficult to make direct comparisons. For instance, manufacturer A could offer amodule which includes IEC fault level studies and IEEE 1584 arc flash evaluation as one complete package, whereas manufacturer B will offer them as separate modules. I have also seen very useful additional features, such as direct current arc flash evaluation, thrown in as free features where the same feature may be an expensive separate module from another manufacturer.

Learning Points
  • Make a shopping list of exactly what functionality you require.
  • Try before you buy. Most companies provide a free month (with reduced functionality).
  • The cost is usually driven by the number of nodes or buses.
  • Make sure that the software will deliver reports, labels, and paperwork to local standards.
  • Factor in training costs.
  • Check technical support standards.