The use of structural metal as a grounding electrode is an issue that has been revised during several recent Code cycles. The 2011 NEC has once again revisited the rule explaining when a structural ...
All Code references are based on the 2005 NEC. The grounding and bonding requirements in this column apply to solidly grounded systems that operate at not more than 600V, such as 120/240V, 120/208V, ...