Control panel markings can be found on every control cabinet, where they serve an important function. This article explains what that function is and what types of UL markings exist.
Relation to UL
A UL mark in a control cabinet indicates that it has been designed and manufactured in accordance with standards. With a UL mark, anyone can immediately see that the control cabinet meets, at a minimum, the required quality standards.
What are control panel markings or UL markings?
Control panel markings refer to specific markings on an electrical control cabinet. These are applied in the form of a sticker or label and certify that the control cabinet complies with certain standards. If these are the standards set by the well-known testing laboratory UL, they are referred to as UL markings or UL labels.
Are control panel markings required on control cabinets?
From a legal standpoint, UL markings are not required on a control cabinet. However, it generally makes little sense to export a control cabinet to North America without the appropriate label. Underwriters Laboratories (UL)is the oldest government-recognized private testing laboratory in the United States and has established a prominent position there over the course of its more than 100-year history.
Without UL marking, things often just don’t work
Many wholesalers include only products bearing a UL mark in their product lines, and insurance companies often insist on the exclusive use of such products. However, UL marks have another important significance. Any industrial facility intended for operation in the United States must be approved by the relevant authority (known there as the Authority Having Jurisdiction, or AHJ for short). This process can be significantly simplified by having the appropriate UL marking.
Control Panel Markings from Other Laboratories
Since UL is not a government agency but “merely” a state-recognized, private testing laboratory, other companies can, of course, also issue control panel markings. Intertek, FM, and TÜV Süd do so as well and are also recognized by the U.S. Occupational Safety and Health Administration (OSHA). However , their certifications are often not accepted. The insurance companies mentioned, which expressly require UL certification, are an example of this.
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What types of UL markings are there?
There are a wide variety of UL markings. Some of them are only relevant in such specialized areas that even UL itself does not mention them in most overviews intended for end customers and consumers. Others, while more common, do not play a role as control panel markings. For this reason, we will limit ourselves here to the labels that are relevant to control panel construction or that a buyer of a control panel might encounter.
UL Listing Mark
The UL Listing Mark is UL’s best-known certification mark and can also be found on our control cabinets. It confirms that the finished product complies with the relevant UL standards (UL Listed). To verify this, representative samples of the product were tested and evaluated by UL. The manufacturer must undergo regular inspections to ensure ongoing compliance with UL standards.
Recognized Component Mark
Anyone who buys a ready-made control cabinet will normally have little to do with the Recognized Component Mark. This label is only awarded to components that are part of a UL-certified end product. For us as a control cabinet manufacturer, however, such components are essential, as they facilitate the approval of the end product. With components bearing a Recognized Component Mark, it is immediately apparent that they have already been evaluated by UL and meet certain minimum requirements.
The easier it is to obtain UL certification for the end product, the lower the costs will naturally be. In this way, end customers do indeed benefit indirectly from the presence of a Recognized Component Mark.
UL Classification Mark
The UL Classification Mark also confirms that a final product complies with UL standards; however, only certain aspects were tested. For example, the safety of a product bearing this UL marking can only be considered assured under certain environmental conditions, or the testing may have addressed only a portion of all potential hazards. This UL marking is therefore not as comprehensive as the UL Listing Mark.
Field Evaluation Label
Similarly, one of the Field Evaluation labels is not typically found on a control cabinet. Why, then, is it mentioned here? Because while it may not be found on the control cabinet itself, it is likely to be found on the equipment it controls. If such a system is inspected by UL at its location—for example, on the production floor—as part of a field evaluation, it may bear a Field Evaluation Label, which facilitates the granting of an operating permit by the Authority Having Jurisdiction.
Although the UL Listing Mark mentioned earlier is not directly related to field evaluation, it can significantly simplify the process, as it demonstrates that the control cabinet already complies with UL standards, thereby substantially reducing the testing effort.
UL markings complement each other
In addition to those mentioned, there are a number of other UL labels; however, these do not typically play a role in control panel construction, so we will not examine them in detail here. It is more important to note something else at this point: As has been shown, the various UL markings do not simply coexist but complement one another: The UL Recognized Component Mark facilitates the certification of a control cabinet and thus the granting of the UL Listing Mark, which in turn can facilitate the acquisition of a Field Evaluation Label.
When used correctly, UL markings therefore help ensure faster and more cost-effective approval of a product or even an entire system. This applies to both approval by UL itself and by the relevant authorities in the United States.
The Future of UL Markings
UL has recently introduced two new versions of its labels: the UL Enhanced Certification Mark and the Smart UL Certification Mark. According to the company, this move is in response to new market requirements in the area of product safety. Important: The Enhanced and Smart Marks are not new labels, but rather additions to existing marking types, namely the UL Listing Mark and the UL Classification Mark.
Enhanced UL Certification Mark
The new UL markings include at least one additional field containing more detailed information about the certification. As a result, each UL certification is now assigned to a specific category to which it applies. The “SAFETY” category indicates that the product has been certified for safety, whereas “ENERGY” indicates that the certification pertains to energy efficiency, and so on. In addition, the same field includes a country code (US, EU, etc.) that indicates the geographical scope of the marking. Using a unique ID (e.g., E12345), further information about this specific approval can be retrieved from the UL database.
Smart UL Certification Mark
The Smart UL Certification Mark contains the same information as the Enhanced UL Certification Mark, but includes a QR code that directs the user directly to the corresponding page in the UL database. It thus offers an even more convenient way to access the available information. However, the use of these new labels is by no means mandatory for manufacturers; rather, it is simply an option to provide their customers with additional information about the respective certification at a glance.
Zusammenfassung
Control panel markings, also known as UL markings, are labels that serve as visible evidence that a control panel has been tested and approved in accordance with the relevant UL standards. UL markings are of great importance for exports to the United States and Canada. There are a variety of UL markings; however, both exporters and end customers should pay particular attention to ensuring that their control cabinet bears a UL Classification Mark.
