RV Pedestal Bonding

[horses]

I was @ an RV Resort and ran into something that I wanted clarification on so here goes. The park has (39) pedestal's and each one has (1) 2p50A breaker, (1) 1P 30A breaker, and (1) 1P20A breaker along with a driven ground rod . There is no "Main Service Panel" on site that feeds them, but what is there is (3) pad mounted utility transformers that supply power to the (39) pedestals so there is no way to kill the power if needed to service any of the pedestals without contacting the local utility company. My question is where is the required bonding of the EGC and the grounded "Neutral" conductor required to happen, in the transformers? There is no EGC ran with the utility conductors that are ran around the park and stopping periodically and turned up into quazite junction boxes so they can feed a certain amount of pedestals. I'm used to seeing the parks have a main panel onsite that's fed from the utility transformer and in the main panel is where all the bonding of the equipment grounds and neutrals take place, and from there they run (4) conductors to the pedestal where the EGC and the grounded "Neutral" conductor are isolated @ each pedestal and some drive a rod and some don't based on their interpterion of the code and the definition of a "Structure", but that's another topic for another day. Thanks in advance for you feedback.

 

[jap]

The bond would take place in the pedestal.
The Neutral conductor from the utility transformer to the pedestal is the fault current return path.
An EGC would "not" be pulled from the utility transformer to the pedestal. To do so would create a parallel return path for the fault current.
Once the Neutral is landed on the Neutral bar in the pedestal, and, is bonded and grounded, that's where the Equipment Grounding Conductor would originate.
A separate Neutral and Equipment Grounding conductor would be pulled from that point on.

JAP>

 

[horses]

So if I'm understanding correctly, you are basically treating each of the (39) pedestals as a main service and bonding the the Grounded "Neutral" conductor and the EGC @ each pedestal because they are all being fed by an underground utility company loop around the park which doesn't have an EGC ran with those feeders. As I mentioned in my initial post, Im used to seeing the pedestals fed from a panel or panels onsite and having the EGC and neutal isolated @ these pedestals. Also all have their own meter that I'm told the park owns. Thanks again for you feedback.

 

[LarryFine]

My question is where is the required bonding of the EGC and the grounded "Neutral" conductor required to happen, in the transformers? There is no EGC ran with the utility conductors that are ran around the park and stopping periodically and turned up into quazite junction boxes so they can feed a certain amount of pedestals.

That's normal; there is no EGC run with service conductors. The premises EGC system starts at the main disconnect; the three breakers in the pedestals in this case.

I'm used to seeing the parks have a main panel onsite that's fed from the utility transformer and in the main panel is where all the bonding of the equipment grounds and neutrals take place, and from there they run (4) conductors to the pedestal where the EGC and the grounded "Neutral" conductor are isolated @ each pedestal and some drive a rod and some don't based on their interpterion of the code and the definition of a "Structure", but that's another topic for another day.

In those cases, they are feeders, not service conductors, and the pedestals equivalent to sub-panels.

 

[LarryFine]

So if I'm understanding correctly, you are basically treating each of the (39) pedestals as a main service and bonding the the Grounded "Neutral" conductor and the EGC @ each pedestal because they are all being fed by an underground utility company loop around the park which doesn't have an EGC ran with those feeders.

Bingo. Main panels vs sub-panels. And I do believe the pedestals should have electrodes; they're more than branch circuits with single disconnect switches.

 

[kwired]

The question becomes is this permitted to allow each one to be service equipment?

First they would have to be listed/identified as SUSE. I don't think any the RV pedestals I have encountered are.

 

[LarryFine]

The question becomes is this permitted to allow each one to be service equipment?

First they would have to be listed/identified as SUSE. I don't think any the RV pedestals I have encountered are.

Doesn't that suggest they should be preceded by OCP and wired as sub-panels with feeders?

I.e., the OP is correct.

 

[kwired]

Doesn't that suggest they should be preceded by OCP and wired as sub-panels with feeders?

I.e., the OP is correct.

I guess that was kind of my point.

I don't think you can split the service into so many directions as a general rule. Specific allowance is mentioned to have a dwelling and an accessory building to be served this way. On the farms it kind of always was done that way, though I don't know strict reading of NEC really allows that as much as I see it done. Many rural locations even if they really don't have any 547 applications have always run service conductors for multiple structures to a central distribution pole.

 

[horses]

The question becomes is this permitted to allow each one to be service equipment?

First they would have to be listed/identified as SUSE. I don't think any the RV pedestals I have encountered are.

That my question.

 

[horses]

Doesn't that suggest they should be preceded by OCP and wired as sub-panels with feeders?

I.e., the OP is correct.

Not on here much, but just curious what " the OP is correct" other person

 

[LarryFine]

Not on here much, but just curious what " the OP is correct" other person

Original Poster, aka the thread starter.

 

[horses]

Original Poster, aka the thread starter.

Thanks!

 

[horses]

Doesn't that suggest they should be preceded by OCP and wired as sub-panels with feeders?

I.e., the OP is correct.

Was it ever determined if the (39) pedestals are allowed to be considered service equipment ans have the EGC and grounded neutral bonded @ each campsite or is this particular installation meeting code requirements.

 

[kwired]

Was it ever determined if the (39) pedestals are allowed to be considered service equipment ans have the EGC and grounded neutral bonded @ each campsite or is this particular installation meeting code requirements.

I think most places would require 1-6 service disconnecting means grouped at one location ahead of the pedestals and I think that would be the intent of NEC as well even though it may not be totally clear about it.

A single site for an RV could also have the pedestal be the service equipment - if it is SUSE. More recent code editions it would need line barriers on top of having neutral that can be bonded. Most RV pedestals I've encountered have two lugs per line for "feed through" purposes. I don't think those types would be SUSE, but can't say I've seen any made after code started requiring line barriers either so maybe they are different now.

 

[horses]

I think most places would require 1-6 service disconnecting means grouped at one location ahead of the pedestals and I think that would be the intent of NEC as well even though it may not be totally clear about it.

A single site for an RV could also have the pedestal be the service equipment - if it is SUSE. More recent code editions it would need line barriers on top of having neutral that can be bonded. Most RV pedestals I've encountered have two lugs per line for "feed through" purposes. I don't think those types would be SUSE, but can't say I've seen any made after code started requiring line barriers either so maybe they are different now.

So with the way the park is currently wired with no main service disconnects after the utility transformers that are feeding the (39) existing pedestals, than each pedestal will have the EGC, The Grounded "Neutral " conductor, and the grounding electrode conductor bonded @ each pedestal location, and that would meet code?

 

[horses]

Thanks again for all of the input! I just have never seen a RV Resort where all the pedestals were wired from 3 utility transformers spread through the park and no main service disconnecting means!

 

[jap]

Thanks again for all of the input! I just have never seen a RV Resort where all the pedestals were wired from 3 utility transformers spread through the park and no main service disconnecting means!

I'm curious as to how the power company is metering the pedestals.

JAP>

 

[horses]

I'm curious as to how the power company is metering the pedestals.

JAP>

Good question! It comes in from the street overhead and then down to the 1st transformer? I guess back when they had it installed they just looked at each lot as it's on main service disconnect, just never seen this kind of installation.

 

[jap]

Good question! It comes in from the street overhead and then down to the 1st transformer? I guess back when they had it installed they just looked at each lot as it's on main service disconnect, just never seen this kind of installation.

Unless it's a special circumstance, I find it hard to imagine that the power company would extend unmetered service conductors to each pedestal.

They are not big fans of giving away free power.
I also don't think the power company would let them dig into their padmounts for power unless the pedestals were individually metered units.

I also do not think they would have installed the conductors themselves or CT'd the power at the transformer which would mean that an electrician would have had to been involved somewhere in all of this.

Generally the power company stops at the meter if it's self contained and that's where the customer or electrician would take over.
I also don't feel there would be enough amp draw on such a service to warrant a CT meter on the pad mounts.

Can you give any more information as to where the utility meters are located for the pedestals?

JAP>

 

[kwired]

So with the way the park is currently wired with no main service disconnects after the utility transformers that are feeding the (39) existing pedestals, than each pedestal will have the EGC, The Grounded "Neutral " conductor, and the grounding electrode conductor bonded @ each pedestal location, and that would meet code?

Does each pedestal have an individual run to the transformer or did they daisy chain conductors between pedestals?

Individual run to each pedestal would comply with 230.2 and 230.40

Daisy chaining them would need to be arranged so that the first one contains the service disconnecting means and the rest would be feeder supplied.

NEC isn't concerned about if there is any metering, though can step in with some rules when metering is present, but for most part a meter is just a "wide point" in the conductors to NEC.

Is certainly possible POCO in this case either has metering on primary supply or maybe CT metering on each transformer secondary.

If this is in say a city park and city operates the POCO there maybe isn't any metering, though most those situations I still see metering as they still want to track expenses to the proper city sub department for budgeting reasons.

This unconventional set up kind of sounds like what you might find when there is a small town municipal POCO and the city has their electric guys who are usually linemen and not commercial installations type electricians install the power in the RV park. They don't know NEC rules for the most part, and because they are a utility seem to think they are exempt from following NEC or getting permits and inspections. City council isn't hiring an EC to do this when they already have an "electrical crew" even though they don't understand differences in qualifications, licensing, etc. I see this in parks and other city owned facilities all the time when the city has it's own municipal POCO.