grounding of 600 amp single phase service w/ three 200 amp disconnects

[CECO]

new installation of a single phase 600 amp service. ct cabinet and three 200 amp disconnects outside of building/ tsparkyhree 200 amp load centers inside. plan to ground each disconnect w/#4 ground conductor, are two rods required for each disconnect?

 

[iwire]

new installation of a single phase 600 amp service. ct cabinet and three 200 amp disconnects outside of building/ tsparkyhree 200 amp load centers inside. plan to ground each disconnect w/#4 ground conductor, are two rods required for each disconnect?

No, you don't need a six ground rods.

You have to have one grounding electrode system and all electrodes must be tied together.

The size of the GEC is based on the size of the service conductors not the rating of the disconnects.

 

[kwired]

There is more then one way to do this, and type of elecrode(s) present also factor into it.

If rod(s) are the only electrodes present a single 6 AWG GEC is all that is needed. You do need a bonding jumper between disconnects though sized per 250.66 or tie the GEC to a common point if available ahead of the service disconnects.

Same goes for if a CEE is only present elecrode except you must use at least 4 AWG for the GEC.

If you have water pipe or building steel electrodes you can run individual GEC sized per supply conductors to each disconnect, or sum the supply conductors and size single GEC for all three disconnects and make individual taps to the larger GEC sized per each disconnect. I typically run the full sized GEC to one of the disconnects and a smaller tap to the other two.

There could be a couple other variations on how to do this.