On a pad mount transformer, how are the bonding jumpers sized that bond the metallic raceways (grounding bushings)within the primary and secondary sections? Thanks, Tom

Tom, suggest 1999 NEC 250-80, 250-102(c), 250-28(d) assuming this is an Utility Co. transformer, other wise 250-30 for secondary side and 250-122 for primary side.



[This message has been edited by Glenn (edited 11-06-2001).]

If this is an exclusively utility controlled xfrmr, the NEC isn't applicable per 90-2(b)(5). You would need to get the spec from the serving utility.