Ground rod required?

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judy1205

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Our former building official insisted on requiring a ground rod for a panel (in a detached structure) subfed with 4 wires and grounds and neutrals separated in panel. Recently, this interpretation has been challenged and we have not been able to pin down the correct Code reference. Any help?:?
 
250.32 Buildings or Structures Supplied by a Feeder(s)
or Branch Circuit(s).
(A) Grounding Electrode. Building(s) or structure(s) supplied
by feeder(s) or branch circuit(s) shall have a grounding
electrode or grounding electrode system installed in
accordance with Part III of Article 250. The grounding
electrode conductor(s) shall be connected in accordance
with 250.32(B) or (C). Where there is no existing grounding
electrode, the grounding electrode(s) required in 250.50
shall be installed.
Exception: A grounding electrode shall not be required
where only a single branch circuit, including a multiwire
branch circuit, supplies the building or structure and the
branch circuit includes an equipment grounding conductor
for grounding the normally non?current-carrying metal
parts of equipment.
 
Can a 4 wire subfeed (2 hots, a neutral and an insulated euipment grounding conductor) be considered a multiwire branch circuit? It seems to meet all the requirements.
 
A MWBC would not need a GES and feeder to a panel would. Also there is no requirement to use a ground rod(s) as the GES. A CEE in the footing would be all that's required as well as any of the other electrodes in Article 250.
 
The op referenced a panel so it is a feeder and not a MWBC. The rods need to be connected to the grounding conductor feeder and the neutral must be isolated from the grounding bar.
 
Branch Circuit. The circuit conductors between the final
overcurrent device protecting the circuit and the outlet(s).
Click to expand...

Branch Circuit, Multiwire. A branch circuit that consists
of two or more ungrounded conductors that have a voltage
between them, and a grounded conductor that has equal
voltage between it and each ungrounded conductor of the
circuit and that is connected to the neutral or grounded
conductor of the system.
Click to expand...

It is still a branch circuit as defined in definitions as see below.

Feeder. All circuit conductors between the service equipment,
the source of a separately derived system, or other
power supply source and the final branch-circuit overcurrent
device.
Click to expand...

since there is OCPD's after this feeder it is a feeder.
 
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