Splicing into service conductors

[JoeNorm]

Here is the situation. I have a 200Amp meter base on unistrut serving a house(3-wire service) about 100 feet away. There is a small structure very near the meter that I want to power. Instead of trenching back from the house I want to "tap" into the service and create a new one for the small structure.

I know the rules for feeder taps but this is not a feeder tap, it would be a service. I don't quite understand the rules here. Can I splice into the 4/0 downstream the meter with 100amp rated wire like I could doing a feeder tap? Is there anywhere in the NEC that spells this out?

Thanks for helping to clarify

 

[letgomywago]

I think that's an outside feeder tap so you'd be good that way but the inspector might call it an altered service and make you put in a disconnect. You'll also need the poco to pull the meter that takes more time. I'd be more inclined to do a standard breaker at the main panel. You can still go overhead with it and not need to worry about someone complaining about grouping disconnects and other possible complaints. If there is a meter main already I'd have to think more about it if you're doing a panel change anyway just put in a 816 metermain with feedthrough and put a breaker in.

 

[electrofelon]

Here is the situation. I have a 200Amp meter base on unistrut serving a house(3-wire service) about 100 feet away. There is a small structure very near the meter that I want to power. Instead of trenching back from the house I want to "tap" into the service and create a new one for the small structure.

I know the rules for feeder taps but this is not a feeder tap, it would be a service. I don't quite understand the rules here. Can I splice into the 4/0 downstream the meter with 100amp rated wire like I could doing a feeder tap? Is there anywhere in the NEC that spells this out?

Thanks for helping to clarify

Sure, see 230.40 exception #3. There will be a set of service conductors and a service disconnect for each structure.

 

[ptonsparky]

Milbank makes a nice little set of lugs that replace the originals and allow for just what you are wanting to do. IDK about any other mfgs.

 

[JoeNorm]

It does look to be perfectly OK based on the NEC. They even specify you don't have to group disconnects in this case

Next question is for the local utility. Technically anything like this requires an altered service application, which usually means upgrading to a meter/main combo with disconnect.

 

[electrofelon]

It does look to be perfectly OK based on the NEC. They even specify you don't have to group disconnects in this case

Next question is for the local utility. Technically anything like this requires an altered service application, which usually means upgrading to a meter/main combo with disconnect.

If you put a meter main in, then they would be feeders and you would need to upgrade to four wire. As long as everything is on the load side of the meter, I would just do it without involving the utility.

 

[JoeNorm]

If you put a meter main in, then they would be feeders and you would need to upgrade to four wire. As long as everything is on the load side of the meter, I would just do it without involving the utility.

True. Around here the inspectors often let the 3-wire stay even though a meter main has replaced the original meter can. But that is often unelected(utility required and initiated) upgrades. I am not sure how the inspector would treat it if it was elected like this.

Would the best way be to add lugs in the meter or do an in-ground splice? I was originally thinking the latter but doing it in the meter would be much easier.

 

[electrofelon]

True. Around here the inspectors often let the 3-wire stay even though a meter main has replaced the original meter can. But that is often unelected(utility required and initiated) upgrades. I am not sure how the inspector would treat it if it was elected like this.

Would the best way be to add lugs in the meter or do an in-ground splice? I was originally thinking the latter but doing it in the meter would be much easier.

Several options. My first choice is usually to put in a 320 meter socket. But they stopped making those (lol) and that could be a can of worms with the utility anyway. Those lugs ptonsparky mentioned are an option if they work. They do only go up to 1/0 conductors FYI.

Milbank - K4977-EXT

www.milbankworks.com

Then of course you could put a box under the meter or underground. I would probably try to avoid the underground splice if possible.

 

[ptonsparky]

1/0 should get you a 100 amp rated service.

Let us know when you actually load that 200 amp meter socket past its rating. Or even close.

 

[electrofelon]

1/0 should get you a 100 amp rated service.

Let us know when you actually load that 200 amp meter socket past its rating. Or even close.

Yeah, I use 320 sockets a lot for this sort of thing where you need two feeds, but it's just for the convenience of the dual lugs, not for capacity. I've never tried those meter sub feed lugs but seems like they would be handy.

 

[JoeNorm]

How bout using tap lugs on the conductors in the meter can? Would there be enough room for those?

 

[ptonsparky]

How bout using tap lugs on the conductors in the meter can? Would there be enough room for those?

I think I bought a set of three in a bag for less than one insulated lug.

 

[electrofelon]

How bout using tap lugs on the conductors in the meter can? Would there be enough room for those?

I would not advise. Not much room and too much potential for POCO having a problem with it, IMO.

I usually set a box next to / under the meter and use Blackburn WR series H taps - they're super cheap like $3.50 each.

 

[LarryFine]

How bout using tap lugs on the conductors in the meter can? Would there be enough room for those?

Not allowed here. We can't even land rod EGCs in meter cans, and it's the perfect place for them.