You run rigid (or any metallic raceway) and you take a EGC to the transformer, you run PVC and parallel paths are not an issue.
Brian, this can be solved by bonding the metalic conduit only at the service end and letting it float in the transformer.
Roger
True BUT 99% of the installs I see are either intentionally bonded or accidently as in poured slab with conduits imbedded in the concrete tied to re-bar and transformer mounted to the slab.
If it is a metallic raceway such as a service trough very hard to avoid.
I think I'm facing that right now. but a little bit different
I have a "U" structure of conduits the stacks are rigid between PVC, the inspector has already told me to bond the ends of each stack, well ok this is the Line side from the transformer it does not drop out of the bottom of the transformer.
So based on this Float statement on the Transformer stack I need to apply bonding bushings and let the line side of the Ground wire back to the MDP ground the stack, I guestioned all this with my Engineer (of record), he's got to talk it out with POCO because my questions got them to a thinking...
So, heres the newest plan, I supply a grounding triad for the building and it will run up to the Transformer vault thats it.
I install a second PVC conduit from the triad to the MDP, that's it, for now.
there calling back Monday...
It's already a Hot summer