first point of disconnect

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Daja7

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I have a question about first point of disconnect.
Residential application. High end development ( not relevant) meter and 2 200 amp main disconnects at property
line the 2 sets of service wires 3+ grnd run underground to house, about 60 feet +-. enters home and then goes to 2, 200 amp panels. We installed a generator and put the transfer switches (2) inside between the panels and wire coming from the mcb outside. Neutrals and grounds already separated in panels and we separated as well in trnsf. switch. Inspector says that the transfer switch is now first point of disc and we must drive new rods and run cold water ground to trnsf. sw.
Just trying to make heads or tales of this. cannot seem to find code section addressing it. Any thoughts?
 
Daja7 said:
I have a question about first point of disconnect.
Residential application. High end development ( not relevant) meter and 2 200 amp main disconnects at property
line the 2 sets of service wires 3+ grnd run underground to house, about 60 feet +-. enters home and then goes to 2, 200 amp panels. We installed a generator and put the transfer switches (2) inside between the panels and wire coming from the mcb outside. Neutrals and grounds already separated in panels and we separated as well in trnsf. switch. Inspector says that the transfer switch is now first point of disc and we must drive new rods and run cold water ground to trnsf. sw.
Just trying to make heads or tales of this. cannot seem to find code section addressing it. Any thoughts?
Click to expand...

I?m under the 2008 NEC so you might want the guys under 2014 to answer.

You did not mention if the original feeder disconnects and now transfer swathes are grouped together.

You would go to article 225 to see if this is being supplied by more than one feeder.

To answer your question the single family dwelling needs a disconnect in addition to the disconnects as you described at another location outside.

The disconnects need to be at the point of entrance of the feeders into the dwelling either inside or outside.

You do need to establish a grounding electrode system at the Dwelling however that would bond to the equipment ground bus and the equipment grounding conductor. At the 4-wire feeder and the main disconnect
 
Lets go back to the service. I understand that there is a meter that is not at the house but 60' away and that there are two 200 amp panels there also. If so and you have 2 feeders coming to the house underground then that is a violation to begin with.
 
Dennis Alwon said:
Lets go back to the service. I understand that there is a meter that is not at the house but 60' away and that there are two 200 amp panels there also. If so and you have 2 feeders coming to the house underground then that is a violation to begin with.
Click to expand...

There is one 400 amp meter two 200 amp disconnects that feed to the house to the panels in the house with MCB's.

We put the transfer sw in between the incoming and panels. The neutral and grnd bonded at the main 200 amp panels w/ grnd rods. He wants the grnd and neutral bonded again at the trnsf sw. This seems like a violation.
 
Dennis Alwon said:
Lets go back to the service. I understand that there is a meter that is not at the house but 60' away and that there are two 200 amp panels there also. If so and you have 2 feeders coming to the house underground then that is a violation to begin with.
Click to expand...

I've never heard of a service set up this way, but since those feeders are fused at the meter base and are no longer service feeders, what section of code would prohibit running two sets of regular feeders to the house?
 
Daja7 said:
I have a question about first point of disconnect.
Residential application. High end development ( not relevant) meter and 2 200 amp main disconnects at property
line the 2 sets of service wires 3+ grnd run underground to house, about 60 feet +-. enters home and then goes to 2, 200 amp panels. We installed a generator and put the transfer switches (2) inside between the panels and wire coming from the mcb outside. Neutrals and grounds already separated in panels and we separated as well in trnsf. switch. Inspector says that the transfer switch is now first point of disc and we must drive new rods and run cold water ground to trnsf. sw.
Just trying to make heads or tales of this. cannot seem to find code section addressing it. Any thoughts?
Click to expand...

As the house constitutes a separate structure from where the main service disconnect is located, you do need rods and cold water ground (if installed) at the house. Now that you've intercepted the feeders, they would need to be attached to the ground on the xfer switches instead of to the panels. If they're existing and will reach the xfer switches, I don't see any need to drive new rods or run new wires to the cold water.
 
Dennis Alwon said:
Lets go back to the service. I understand that there is a meter that is not at the house but 60' away and that there are two 200 amp panels there also. If so and you have 2 feeders coming to the house underground then that is a violation to begin with.
Click to expand...

Where is the structure disconnect means distance requirement in the NEC code? There is a disconnect means outside of the structure. Or how far one can enter a building if the feeder disconnect is place inside as allowed?
 
Art. 225.30-- number of supplies.

225.30 Number of Supplies. A building or other structure
that is served by a branch circuit or feeder on the load side
of a service disconnecting means shall be supplied by only
one feeder or branch circuit unless permitted in 225.30(A)
through (E). For the purpose of this section, a multiwire
branch circuit shall be considered a single circuit.
Where a branch circuit or feeder originates in these additional
buildings or other structures, only one feeder or
branch circuit shall be permitted to supply power back to
the original building or structure, unless permitted in
225.30(A) through (E).
(A) Special Conditions. Additional feeders or branch circuits
shall be permitted to supply the following:
(1) Fire pumps
(2) Emergency systems
(3) Legally required standby systems
(4) Optional standby systems
(5) Parallel power production systems
(6) Systems designed for connection to multiple sources of
supply for the purpose of enhanced reliability
Click to expand...
 
mwm1752 said:
Where is the structure disconnect means distance requirement in the NEC code? There is a disconnect means outside of the structure. Or how far one can enter a building if the feeder disconnect is place inside as allowed?
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See above-- only one feeder per structure unless you meet the exceptions. You cannot have 2 - 200 amp feeders feed the building as mentioned above
 
Touche! well done -- They allow multiple service laterals (Max 6 separate disconnects )to be mounted on a structure(outside as allowed) yet if you set those same disconnects are set apart from the building (outside as allowed) you interprete only one of the disconnects may serve the building as a feeder. Even though the set of service disconnects are considered 1 service.
The code consider that the group of set apart from the building disconnects to be the disconnecting means therefore all feeders (multiple) to that structure on the load side of the disconnecting means are allowed.
 
I see a couple of problems. First is the fact that, as Dennis points out the original install is in violation and secondly could be in 225.36 as to the T/S being allowed as the disconnect means.
If I were to accept the two feeders and the T/S as the disconnects, I would agree with your inspector and required a grounding electrode system be connected to each T/S.
 
Daja7 said:
meter and 2 200 amp main disconnects at property
line the 2 sets of service wires 3+ grnd run underground to house, about 60 feet +-. enters home
Click to expand...

That right there is the violtion people are mentioning.

You ran two feeders to one structure. While in some cases that is allowed I am 99% sure it is not allowed for this installation.

To comply with code you would need to run one 400 amp feeder to the home and spit it two ways at the home. See 225.30 that Dennis posted above.
 
augie47 said:
I see a couple of problems. First is the fact that, as Dennis points out the original install is in violation and secondly could be in 225.36 as to the T/S being allowed as the disconnect means.
If I were to accept the two feeders and the T/S as the disconnects, I would agree with your inspector and required a grounding electrode system be connected to each T/S.
Click to expand...

I second that. The first point of disconnect just seems to me to be where you need to do the grounding, from there, it's separate neutral and ground.
 
iwire said:
That right there is the violtion people are mentioning.

You ran two feeders to one structure. While in some cases that is allowed I am 99% sure it is not allowed for this installation.

To comply with code you would need to run one 400 amp feeder to the home and spit it two ways at the home. See 225.30 that Dennis posted above.
Click to expand...

so, transformer to ct can split to 2 separate 200A disconnects.
Line & load connections are tied together once at the transformer & inside the CT can.( if mounted on a structure there would be now issues for all here. but they are outside & remote)
Service disconnecting means can be up to six switches and shall be grouped.
load of service diconnect are now outside feeders/service entrance conductors - A building or other structure that is served by a branch circuit or feeder on the load side of a service disconnecting means shall be supplied by only one feeder. The disconnecting means consist of 2 separate 200A disconnects if each disconnect supplies one feeder to the building is there a violation. Otherwise, you are going to limit the service disconnecting means to a single handle - there is no defined place of outside the structure as being attached to or 500' away from only readily accessible.
 
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