The National Electrical Code notes that an industrial control panel is an assembly of two or more power circuit components/control circuits, as well as a mix of the two along with the necessary terminals and wiring. Combine this with the need to be contained inside an enclosure and sub panel, and you fully understand the sheer complexity of one given panel. This includes any UL508A industrial control panels in Denver that you may work with. Because of the complexity of said work, it’s not a huge surprise that many regulatory bodies and electrical inspectors say that it’s necessary for any panels to be listed by a Nationally Recognized Testing Laboratory (NRTL). But why exactly is this the case? Let’s take a closer look.
The major reason that this is the case is for safety reasons. After all, if you were to give an electrical inspection, the reason is to make sure that you classify the installation properly. However, there are some roadblocks for people trying to do their jobs. Every single part of a control panel would need inspection in this case. However, this would be nearly impossible to do in a timely manner if you have to deal with every single component. The alternative is having the panel being approved by letter, but this puts in an additional cost as well as a delay when it comes to getting the project done. The best way to have the best of both worlds in these regards is getting your control panel NRTL labeled.
Several common control panels are labeled in case this happens, with Underwriters Laboratories being one of the most popular options in that regard. However, this can’t always be the case. If you have an industrial control panel that is unlisted, and want to make sure you are prepared when it comes to inspecting your panels, there are options. For example, Underwriters Laboratories has field reps you can bring on to evaluate a panel that is already installed. There are also several other OSHA-accredited companies that can perform this service. If you want a secondary option, you can take out the control panel and send it to a professional panel shop in order to get it listed, along with any other modification and examination needs you have. However, this is rarely the most efficient option in terms of time or money. With this said, there are other situations where you may need to consider how you are going to get your panels inspected. For example, UL 508A is only one set of guidelines. If you end up having a panel installed in a hazardous area, make sure you are compliant with other standards as well.