Could someone please shed some light on this debated issue. Lets say I have a 2000 Amp, 3ph, 120/208V Wye connected service with 6 sets of 500MCM. My transformer is pad mounted and supplied by the utility. The conduit is PVC schedule 40. Of course I have 3 phases and 1 neutral per conduit. The question is.. Do I need to also pull in a fifth conductor for ground? I have seen this engineered both ways. Do I need the fifth conductor? If so, where does it terminate at the transformer? Does it make any difference if the conduit is Rigid Steel?
Service Entrance Grounding Electrode Conductor
- Thread starter derwood14
- Start date
- Status
- Location
- Massachusetts
Re: Service Entrance Grounding Electrode Conductor
Absolutely not.
The power company transformers XO is bonded to the transformer case.
Your service gear has its neutral bonded to the enclosure.
Any grounding conductor run between these pieces of equipment becomes a conductor in parallel with the neutral conductor run between these pieces of equipment.
Another way to look at it is this.
On a service to a house is there a grounding conductor between the house panel and the power company transformer?
It is the same thing only in a smaller scale.
[ February 10, 2005, 06:21 PM: Message edited by: iwire ]
Absolutely not.
The power company transformers XO is bonded to the transformer case.
Your service gear has its neutral bonded to the enclosure.
Any grounding conductor run between these pieces of equipment becomes a conductor in parallel with the neutral conductor run between these pieces of equipment.
Another way to look at it is this.
On a service to a house is there a grounding conductor between the house panel and the power company transformer?
It is the same thing only in a smaller scale.
[ February 10, 2005, 06:21 PM: Message edited by: iwire ]
charlie
Senior Member
- Location
- Indianapolis
Re: Service Entrance Grounding Electrode Conductor
FWIW, we prohibit any customer's grounding conductors to be connected in any of our equipment. We will permit almost any type of raceway to be installed for the service conductors but the ell and stub up must be PVC or we will not accept the installation.
FWIW, we prohibit any customer's grounding conductors to be connected in any of our equipment. We will permit almost any type of raceway to be installed for the service conductors but the ell and stub up must be PVC or we will not accept the installation.
- Location
- Massachusetts
Re: Service Entrance Grounding Electrode Conductor
We often run the primary raceway for the POCO, one of the POCOs specs calls for two runs of 5" raceway.
The straight sections can be concrete encased PVC. The stub up, the large radius sweep and the first 10' horizontal from the sweep must be RMC.
We also must provide bonding bushings.
Charlie does this apply on the primary side as well?Originally posted by charlie:
the ell and stub up must be PVC or we will not accept the installation.
We often run the primary raceway for the POCO, one of the POCOs specs calls for two runs of 5" raceway.
The straight sections can be concrete encased PVC. The stub up, the large radius sweep and the first 10' horizontal from the sweep must be RMC.
We also must provide bonding bushings.
charlie
Senior Member
- Location
- Indianapolis
Re: Service Entrance Grounding Electrode Conductor
Bob, we always provide PVC for our primary cable. We sidestep all grounding problems by insisting on non-metallic conduit. We tie to our system neutral from the primary cable, drive a 5/8" X 10' ground rod, connect to the X0, and bond everything together.
Bob, we always provide PVC for our primary cable. We sidestep all grounding problems by insisting on non-metallic conduit. We tie to our system neutral from the primary cable, drive a 5/8" X 10' ground rod, connect to the X0, and bond everything together.
physis
Senior Member
Re: Service Entrance Grounding Electrode Conductor
Years and years ago I put up a private service pole. It was standard practice in the area (rural) to use PVC up to the weather head. The power company tried to nit pick every possible angle to fail it because I used RMC instead of PVC. Of course it passed anyway.
I partly understand this, but not entirely. What gives Charlie?
Years and years ago I put up a private service pole. It was standard practice in the area (rural) to use PVC up to the weather head. The power company tried to nit pick every possible angle to fail it because I used RMC instead of PVC. Of course it passed anyway.
I partly understand this, but not entirely. What gives Charlie?
charlie
Senior Member
- Location
- Indianapolis
Re: Service Entrance Grounding Electrode Conductor
That is different and probably the same reason that we do not permit grounding on a junction pole. When we climb a pole that has grounding on it (the pole has to have a pole ground all the way to the ground rod), the lineman's leg will be against the pole ground and provide a better path in case of an accidental contact with the primary.
I suspect that the REMC has the same reason in mind.
That is different and probably the same reason that we do not permit grounding on a junction pole. When we climb a pole that has grounding on it (the pole has to have a pole ground all the way to the ground rod), the lineman's leg will be against the pole ground and provide a better path in case of an accidental contact with the primary.
I suspect that the REMC has the same reason in mind.
- Status