Connecting Meter base to Exterior Panel/Disco

[ivsenroute]

On an exterior, wet location, how do you prefer to connect the meter base to the exterior mounted disco/panelboard? If you were connecting it with a 2" conduit, what material and connectors would you use?

Lets assume single phase 240.120 service

 

[Mgraw]

Below the meter base with a hub, 4" long nipple, and 2 locknuts.
Edit: Also a bushing.

 

[mcclary's electrical]

On an exterior, wet location, how do you prefer to connect the meter base to the exterior mounted disco/panelboard? If you were connecting it with a 2" conduit, what material and connectors would you use?

Lets assume single phase 240.120 service

I would do it side by side, rather than over/under. All you need is one coupling and two chase nipples. or one offset nipple and two chase nipples. No locknuts, no bushings

 

[Mgraw]

I tried that once and got a rejection. Inspector said I needed to bond the nipple with a bonding bushing.

 

[cadpoint]

I think your question has to many possible variables not expressed in the op to answer correctly!

It's 120/240 not 240.120, I frankly found myself looking for article 240.120(that doesn't exist).

Let me state 250.8 to start, or 250.3 since the op wasn't specific.

 

[kwired]

Meter - main in one unit is easier and looks better. Using one with branch breaker spaces can be useful for feeding nearby air conditioner separate building or other items. I also use a Milbank model that has an optional interlock kit to allow installing a backfed breaker from a generator. This is about the least expensive way I have seen to allow for a manual transfer switch if you are installing a new service anyway.

 

[e57]

M/M combo - one shot one kill - slapper up - then the rest just inside or a feeder someplace nice. M/M w/dist. - only if I'm replacing the same...

But if I gotta - 2 listed bonding lock-nuts (steel), 2 regular lock-nuts (steel) - sealing if needed, two plastic bushings, one RMC nipple. (Cause I can't use anything else - local code) With a chisle in the rotohammer - tight.

 

[mcclary's electrical]

I tried that once and got a rejection. Inspector said I needed to bond the nipple with a bonding bushing.

On PVC,?????,,,,,hmmmmmm,,,that's strange

 

[Mgraw]

I have not seen a pvc chase nipple. You have a source for those?

 

[mcclary's electrical]

I have not seen a pvc chase nipple. You have a source for those?

You can get these anywhere. Glue it right in a coupling.

http://www.drillspot.com/products/577411/cantex_industries_5133719c_1-1_2_pvc_box_adapter_pack_of_10?s=1

 

[Dennis Alwon]

I have not seen a pvc chase nipple. You have a source for those?

They are not a true chase nipple since there are no threads but that's what I cal them also. They are a life saver.

Any inspector who fails this install because of a bonding bushing obviously does not understand bonding at all.

 

[Mgraw]

I have not used those before nor have I ever seen them used anywhere. I guess one can learn something new all the time.

 

[Mgraw]

We have four POCOs and multiple jurisdictions. They all have their own variations on how things need to be done. Since the State adopted a unified (statewide) code juridictions are getting closer to the same rules. The rejection I got on the bonding bushing (several years ago) was from a young guy whose father was an EC. Everything had to be done the way his father did it.

 

[Cow]

We call them box adaptors. I really don't care to use them since you can't disassemble them without cutting them apart. I will use them when I can't have an MA, locknut, and pb sticking to far into a box(i.e. control cabinets).

 

[wawireguy]

PVC with box adaptors or lock nuts.

 

[Philip Barr]

You can get these anywhere. Glue it right in a coupling.

http://www.drillspot.com/products/577411/cantex_industries_5133719c_1-1_2_pvc_box_adapter_pack_of_10?s=1

I think their usually referred to as TA's or box adapters, I don't like them all that much though, sometimes the couplings your gluing them into are shorter than the box adapter and it ends up loose which obviously is not water tight, not to mention their irreversable in case you have a brainlapse. Many municipalities require a sealing bushing or lockring of some sort even if your in the lower 2/3rd area of the 3R enclosure.
I prefer side by side with PVC if local code and Elec Company allows, otherwise a GRC nipple 2 sealing lockrings for the exterior of the enclosure, 1 bonding bushing 2 regular lockring and 1 threaded plastic bushing.

 

[Mgraw]

Most residential panels are outside in my area. Almost all are meter socket above panel. Some of the newer construction has the panel in the garage.

 

[ivsenroute]

I can't see the over/under approach to installation because of the meter base height requirements and ergonomics for the disco/main panel then being too low.

I am more specifically looking at how they are joined to comply with 312.2, last sentence in the paragraph before the exception.

I do no believe that RMC with a regular locknut on the outside and duct seal is meeting the intent of the code. Especially where it enters a concentric knock out.

 

[Mgraw]

The RMC enters the bottom of the meter socket, below any live parts. The top of the panel has a hub that the RMC screws into. I don't see the problem. The meter socket is installed at 78 inches to the center of the meter.

 

[augie47]

I can't see the over/under approach to installation because of the meter base height requirements and ergonomics for the disco/main panel then being too low.
.

Not sure of the ergonomics, but "Code-wise", I don;t think there is a "too low"

I am more specifically looking at how they are joined to comply with 312.2, last sentence in the paragraph before the exception.

I do no believe that RMC with a regular locknut on the outside and duct seal is meeting the intent of the code. Especially where it enters a concentric knock out.

As far as 312.2 is concerned, the factory knockouts in meter bases are normally below the "level of uninsulated live parts" reference in 312.2 so sealing is not required. (I've seem some base where the biggest knockout may not be fully below the lug level but the fact that the factory KOs are there it is usually confided to be)
Most folks here tie the two together with PVC so as not to be concerned with bonding the nipple