Effective December 23, 2019
ADDENDUM SUN: This ADDENDUM establishes the Continuing Certification approach to Enclosures for Electrical Equipment, and Extends the Effective Date to December 23, 2019. This ADDENDUM replaces SUN issued November 2, 2015.
Effective Date (see Schedule below): December 23, 2019
Overview of Changes:
The 13th edition of UL 50 was issued to include the following requirements:
Current Listings Not Active? – Please immediately identify any current Listing Reports or products that are no longer active and should be removed from our records. We will do this at no charge as long as Intertek is notified in writing prior to the review of your reports.
The second edition of UL 50E includes the addition of environmental Type ratings 3X, 3RX, and 3SX.
|6.5||Info||Cast metal enclosures|
|6.5.5||Additions to existing requirements are underlined and deletions are shown |
An enclosure may be constructed of iron, steel, copper, brass, or aluminum cast metal. Aluminum-base cast metal containing less than 80% aluminum shall not be used. Magnesium-base cast metal shall not be used. Zinc-base
|6.7||Info||Covers and doors|
|188.8.131.52||New clause added;|
The enclosure shall be constructed so that all doors are able to be opened to a minimum of 90° from the closed position.
|6.10||Connections for wiring systems|
|184.108.40.206||Info||Additions to existing requirements are underlined and deletions are shown |
A separable or integral clamp provided
|220.127.116.11||New clause added;|
A separable or integral clamp provided as part of a factory assembled enclosure and intended for securement of nonmetallic-sheathed cable shall substantially close the opening in the enclosure as determined by the following:
b) the clamp shall be provided, at the factory, with a means to individually close each opening.
|9||Info||Cabinets and Cutout Boxes|
|9.1.1||Additions to existing requirements are underlined below.|
In Mexico and the United States, a cabinet or cutout box shall comply with the requirements for enclosures. However, the requirements in Clause 9.2 shall supersede equivalent requirements for enclosures. In Canada, this requirement does not apply.
|9.2||New section added;|
Sheet metal cabinets
|18.104.22.168||The front flange of each of the two side walls of a Type 1 enclosure intended for use with a panelboard may have one notch to accommodate means for installing the cover. Each notch shall not be more than 17.5 mm (11/16 inch) wide.|
|9.2.2||Slot and tab fastenings|
|22.214.171.124||Slot and tab fastenings, consisting of a small cutout on the inner flange surface and a
tab created by pushing in a small segment of metal from the overlapping flange, are
considered as an acceptable fastening only when used in Type 1 enclosures and are
used in combination with a rivet, weld, bolt, or screw having machine screw threads in
at least one of the following locations on each length of a flange:|
a) At the back edge of the enclosure, provided that the distance between the fastenings (including the slot and tab fastenings) comply with Clause 126.96.36.199; or
b) Joining adjacent sides, including a top or bottom side, to comply with Clause 188.8.131.52, except that a rivet, weld, bolt or screw having machine screw threads shall be used to secure the front edge of the enclosure in accordance with Clauses 184.108.40.206 and 220.127.116.11.