Modified:
UL 50 and UL 50E, the two essential UL standards on Enclosures for Electrical Equipment, have just been updated. Here’s a quick review of each of these two important publications and their changes:
UL 50, 13th Edition, Enclosures for Electrical Equipment, Non-Environmental Considerations
The UL 50 applies to enclosures for electrical equipment intended to be installed and used in non-hazardous locations. You’ll use this standard with the Canadian Electrical Code, Part I, CSA C22.1, the National Electrical Code, NFPA 70, and Mexico’s Electrical Installations, NOM-001-SEDE. Coverage is provided for enclosures for indoor locations (Types 1, 2, 5, 12, 12K, and 13) and for Enclosures for indoor or outdoor locations (Types 3, 3X, 3R, 3RX, 3S, 3SX, 4, 4X, 6, and 6P.)
Changes in this new edition are found for the following:
- The addition of environmental type ratings 3X, 3RX, and 3SX
- Sharp edges on electrical equipment
- Requirements for slot and tab fastenings
- Clarification of types of cast metal suitable for use as an enclosure
- Equipment door opening 90 degrees from the closed position
- Certification Requirement Decision for nonmetallic-sheathed cable clamps
- Revision to requirement of cover and flange overlap for cabinets used as panelboards
- Revision to Annex B references
UL 50E, 2nd Edition, Enclosures for Electrical Equipment, Environmental Considerations
Coverage for the UL 50E is the same as the UL 50. However, the standard covers additional environmental construction and performance requirements for enclosures. These used to be part of the UL 50, however in 2007 THESE environmental condition considerations were moved over to the UL 50E standard.
Changes in this 2nd Edition include the following:
- The addition of environmental type ratings 3X, 3RX, and 3SX
- Revisions to the Gasket Compression Test
- Brass inserts for enclosures
- Revisions to specify tightening torque for field installed screws and fasteners critical to maintaining the environmental integrity of an enclosure
- Elimination of Hand Flexing Test for Gaskets
Now you need to get your copies of the UL 50 and UL 50E updates. Remember, like many industry standards, these UL documents are covered by the laws of copyright. So you’ll need to use an authorized standards distributor like Document Center Inc. for your purchases.
Standards can be found by searching our online catalog at www.document-center.com. It’s easy to order online and you can rely on the Document Center staff to be available for you should you have any questions. Here’s a link to the order page for the UL 50 and a link to the order page for the UL 50E.
Of course, using and managing a standards collection involves more than just purchasing documents. Contact our staff by phone (650-591-7600) or by email (info@document-center.com) when you have questions or to learn more about the many support services we offer. Make Document Center your standards experts!
