Delta or Wye panelboard????

[Mporter4]

I am feeding a three phase panelboard and the poco transformer is a solid grounding three-phase 480-volt wye system,I have purchased a three-phase 480-volt 4-wire (w/neutral) panelboard.I will not be pulling a (neutral) wire and was wondering if this is acceptable?(note breakers are 480/277 volt rated)
also I will be using the Neutral bar as a equipment grounding bar ( bonded to can).

 

[jumper]

How will you comply with 250.24(C)

(C) Grounded Conductor Brought to Service Equipment.
Where an ac system operating at less than 1000 volts
is grounded at any point, the grounded conductor(s) shall
be run to each service disconnecting means and shall be
connected to each disconnecting means grounded conductor(
s) terminal or bus. A main bonding jumper shall connect
the grounded conductor(s) to each service disconnecting
means enclosure. The grounded conductor(s) shall be installed
in accordance with 250.24(C)(1) through (C)(3).

 

[raider1]

How will you comply with 250.24(C)

(C) Grounded Conductor Brought to Service Equipment.
Where an ac system operating at less than 1000 volts
is grounded at any point, the grounded conductor(s) shall
be run to each service disconnecting means and shall be
connected to each disconnecting means grounded conductor(
s) terminal or bus. A main bonding jumper shall connect
the grounded conductor(s) to each service disconnecting
means enclosure. The grounded conductor(s) shall be installed
in accordance with 250.24(C)(1) through (C)(3).

Are we sure that the panelboard in the OPers question is the service disconnecting means?

Chris

 

[jumper]

Are we sure that the panelboard in the OPers question is the service disconnecting means?

Chris

Nope. Oops. Saw meter and panelboard and assumed service MDP. Assumptions are worthless.

 

[raider1]

Nope. Oops. Saw meter and panelboard and assumed service MDP. Assumptions are worthless.

Not a problem, maybe the OPer can clarify the situation.

Chris

 

[jumper]

Not a problem, maybe the OPer can clarify the situation.

Chris

Thank you Yoda, young padawon (not in age, but experience) still has much to learn.

 

[dkidd]

Saw meter

?

I see POCO and bonded neutral, which would make me think service.

 

[jumper]

?

I see POCO and bonded neutral, which would make me think service.

What if there is meter> disco> panel. Neutral does not have to go to panel.

 

[raider1]

What if there is meter> disco> panel. Neutral does not have to go to panel.

Agreed. Once the service grounded conductor is connected to the service equipment as specified in 250.24(B) then a grounded conductor is not required to be brought to any remote panelboard unless the loads require a grounded conductor.

Chris

 

[LarryFine]

... maybe the OPer can clarify the situation.

Then again, he may not.

 

[Mporter4]

not a service disconnect

not a service disconnect

the poco transformer feeds a disconnect and from that disconnect I am feeding my panel board.

 

[raider1]

the poco transformer feeds a disconnect and from that disconnect I am feeding my panel board.

Then the disconnect would be the service disconnecting means and you must bring a grounded conductor to that disconnect. (See 250.24(C)) Then you must have a main bonding jumper installed at the service disconnecting as well. (See 250.24(B))

From the service disconnecting means to the panelboard you are not required to bring the grounded (Neutral) conductor unless the circuits feed by the panelboard require a grounded neutral conductor.

Chris