Industry needs to revise UL 719 Edgewise Crush test
The NM cable industry needs to be proactive and recommend to UL, changes to the UL 719 Edgewise Crush test for flat Nonmetallic-Sheathed Cable, to make that test more reliable and meaningful.
Manufacturers spend far too much time in making their cables pass this test, which has shown not to be repeatable or reliable. A reliable test is needed to give the manufacturer confidence that their cable will withstand stapling on edge, even though Section 334.30 of the National Electrical Code prohibits stapling on edge. Contractors still do it, and inspectors still see it and order a correction, but sometimes it's let go because in their judgment, the cable doesn't appear to be damaged.
As a starting point, the revisions made in 2007 to improve the Edgewise Crush test procedure in UL 493 (UF cable) should be considered for UL 719 as well.
01-09-2008 3:55 PM