Grounding conductor routed separate from circuit conductors

[greenspark1]

The situation- an existing service panel (call is Z) with a wireway above. The previous electrician installed a 4/0 ground up into the wireway terminating into an insulated busbar. This then runs to the building's water main.

We're adding a new panel (call it Y) 10' away. The new panel will be fed from Z. The electrician want to tap the busbar in the wireway and run a small conduit down to Y for the ground, and run a new conduit from Y to Z with the 4 phase conductors. This is 208/120V. Is this legal to have the ground in a separate conduit than the phase conductors? It feels wrong but I'm having trouble pinpointing anything in the Code, 250.134(B) seems like the right spot. Anyone run into this before???

 

[GoldDigger]

When you say "ground" do you mean the EGC, a GEC or just the current carrying grounded conductor of a wye system?
Normally neither an EGC nor a GEC will connect to an insulated bar.

Tapatalk!

 

[greenspark1]

It's a hybrid The wire is run from the ground bus of service panel Z up to the hunk of copper bus, should have called it a ground bar.

A separate wire (GEC) runs from the ground bar to the water main. This is a GEC, except that it doesn't terminate in panel Z.

It seems like they are trying to combine a GEC and EGC onto one ground bar. I am thinking I should leave it alone and run a standard EGC with the phase conductors to the new panel.

 

[infinity]

The EGC must be run with the feeder conductors. It could be a metallic raceway instead of an EGC within the raceway. Once you have the EGC with the feeder you can run another conduit to the ground bar with a single conductor if you so desire.