What do inspectors look for in your Electrical Control Panel?

Answer: The UL Listed label.

If your electrical panel is part of a permitted construction project, then one of the first things that a local code inspector may look for is the UL Listed label. It is, first and foremost, a sign that the panel meets a safety standard: that it won’t be the cause of a fire. Some large manufacturers want every panel in their plant to be UL Listed.

When Brithinee Electric builds custom control panels, the evaluations we make help us to determine conformance to the applicable requirements of nationally recognized product safety standards, and the acceptability criteria of the local jurisdiction. While ultimate approval of a control panel and its installation lies with the local authority having jurisdiction, it is very often the case that, once the inspector finds the UL Listed label, he is satisfied of its suitability.

For example, the small compressor that you might have in your home’s garage may be labeled as having the performance of  “5 HP.” And maybe by NEMA Standards, the motor really is more like a 2 HP motor. The UL Label is a safety label, and doesn’t in any way imply anything about the horsepower rating.  Of course, the folks at Underwriters Laboratories would prefer not to be embarrassed by a mislabeling of the power rating, but they are not checking that.

What is UL? What about UL Marks and labels?

Underwriters Laboratories (UL) is an independent safety science company that tests and evaluates samples of various products periodically and determines whether that product meet their standards or not. Most (but not all) of these will have a UL Mark on the device itself. (A few may have the UL Mark present on the packaging of a product, but not on the product.)

And, some products which are intended to be used in the manufacture of a complete UL Listed product may come with a UL Recognized Component Mark.

But, an electrical control panel that is built with component pieces, each of which carries a UL Mark or UL Recognized Component Mark, does not automatically qualify the panel to get a UL Listed Electrical Control Panel. There’s a lot more to it than that.

It is a guarantee that your panel is built with high quality and completely tested, physically and environmentally safe components. The spacing, the position, the wire size, etc. must conform to the standards that UL provided (in our case, UL 508A).
What to look for in a UL Listed Electrical Control Panel.

There are four elements in a UL Listing Mark:

  1. UL in a circle
  2. Word “LISTED”
  3. Product identifier
  4. Control or issue number


This label is printed by authorized printing companies, on adhesive material that will be destroyed if someone tries to remove it. These are tightly controlled! They are also very valuable. Ask anyone who has a panel that doesn’t have the label, and an inspector comes looking for it!

What if you have an electrical control panel, and it doesn’t have the proper UL Listed label?  Can this be added in the field?

Yes, in some circumstances.  But this can be costly as it probably will involve inspection and modification by our personnel, and then a visit by a UL inspector at your plant as the UL Listed label is applied. It is much less costly to have the panel built originally to the exacting safety standards of UL 508A, and then appropriately labeled in our controls plant.

In our June newsletter, we will discuss some of the internal design criteria that distinguish a UL Listed Control Panel.

Call our Control’s Department at 909-825-7971 ext. 7 for more information about how to build it right, with UL Listed Labels.