Utilility requires a neutral conductor in service entrance 480Y/277. 480 loads only.

[11bgrunt]

Oilfield serves almost all pump loads with 480 volts delivered by utility with 480Y/277 secondary. Utility?s choice of an overhead service or from a pad mount transformer. At the service entrance in a riser, the utility wants a neutral in the riser down to an insulated neutral buss. In a pad mount transformer, a neutral is also required to go from transformer to the circuit protection panel.
The utility wants a neutral and the customer knows that a neutral will not beused at the load. Three hot legs and a grounding conductor is what will be run to the well.
My position is that a grounding conductor is all that must be connected to the utility.
What code article should I reference?
This utility has no licensing authority. Licensees are tested at the state level.
I contend that the panel must be marked and there is a risk that a load may be connected in the future that would require a neutral to operate.
The oilfield looks at the service entrance for that load only.

 

[iwire]

The situation sounds odd but putting that aside in general if this is a rule in the power companies terms of service they can refuse to connect if it is not done.

 

[david luchini]

250.24(C) requires that the grounded conductor be brought to the service disconnecting means and bonded to the disconnecting means enclosure, if the system is grounded at any point.

This applies even if the grounded conductor will not be used as a circuit conductor.

 

[jim dungar]

Every utility in our area requires a grounded conductor be run between the wye point of their transformer and the customer's service entrance equipment.

 

[iwire]

250.24(C) requires that the grounded conductor be brought to the service disconnecting means and bonded to the disconnecting means enclosure, if the system is grounded at any point.

This applies even if the grounded conductor will not be used as a circuit conductor.

That only applies if the system is grounded at any point.

The power company could leave the XO floating and treat the supply like a delta.

That said I suspect this power companies SOP is to bond XO.

 

[david luchini]

250.24(C) requires that the grounded conductor be brought to the service disconnecting means and bonded to the disconnecting means enclosure, if the system is grounded at any point.

This applies even if the grounded conductor will not be used as a circuit conductor.

That only applies if the system is grounded at any point.

Yes, I know...that's why I mentioned it :happyyes:

That said I suspect this power companies SOP is to bond XO.

I suspect the same.

 

[weressl]

Oilfield serves almost all pump loads with 480 volts delivered by utility with 480Y/277 secondary. Utility?s choice of an overhead service or from a pad mount transformer. At the service entrance in a riser, the utility wants a neutral in the riser down to an insulated neutral buss. In a pad mount transformer, a neutral is also required to go from transformer to the circuit protection panel.
The utility wants a neutral and the customer knows that a neutral will not beused at the load. Three hot legs and a grounding conductor is what will be run to the well.
My position is that a grounding conductor is all that must be connected to the utility.
What code article should I reference?
This utility has no licensing authority. Licensees are tested at the state level.
I contend that the panel must be marked and there is a risk that a load may be connected in the future that would require a neutral to operate.
The oilfield looks at the service entrance for that load only.

Because the Utility is not allowed to install an ungrounded service. The Utilities are allowed to have their internal rules, eg. how they uid their distribution system, but how thye interface with the Customers is regulated. The regulating authority varies from State-to State, in Texas it is the PUC or Public Utility Commissioner.

 

[meternerd]

IF you could get the utility to provide you an ungrounded 480V 3W delta service, you could get away with no neutral, but it's unlikely any utilities would be willing to do so. Delta services are becoming very rare.

 

[texie]

250.24(C) requires that the grounded conductor be brought to the service disconnecting means and bonded to the disconnecting means enclosure, if the system is grounded at any point.

This applies even if the grounded conductor will not be used as a circuit conductor.

You get the prize. This is a very important requirement and a problem I encounter fairly often in the field where the electrician says the neutral is not going to be used. Failure to do this can have lethal consequences when a service is supplied from a grounded POCO source.
I might add that the grounded conductor in this case would have to be, at a minimum, sized to Table 250.66.
In this day and age it would be very rare for a POCO to be willing to supply an ungrounded service. Some mistakenly believe that if they don't install and bond the grounded conductor at the service that they now have an ungrounded service. This would only be true if the POCO does not bond and ground it at their end.