Cable Tray Grounding


Senior Member
When installing IAC cable in cable tray [parallel runs each with a ground conductor in the IAC], is the grounding jumper installed on the cable tray considered a "supplemental ground"? Because the IAC cables carry in each a ground conductor, so the tray would just have to be bonded togerther but what size bonding would you use? Would you have to size it based on the OCPD even though each of the IAC's has a continuous ground or would a supplemental ground size be all that is required?


Senior Member
I don't have much experience with trays, but I would guess the size of the bonding is based on the largest OCPD of the circuit that may energize the tray. If I am wrong I am sure someone will set me straight.

Smart $

Esteemed Member
If all your cables contain EGC's, metallic cable tray only needs to be bonded, sized per 250.122 for the largest OCPD. Pretty much the same as when used as EGC.