millstrainer
Member
How do I determine the size of bonding jumper that is required around concentric KO's? The Metal box has several EMT conduits coming into it of various sizes, They are coming into concentric KO's and are over 250 volts. I know I am going to have to use a bonding bushing on each conduit, but how do I size the required jumper from the bushing to the box? Are each of jumpers based individually on the OCPD protecting the conductor in the conduit, or would every jumper have to be sized based on the largest OCPD protecting the largest conductor entering the box?