The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!


2017 NEC and Related
2017 NEC
Now Available!

Recent Posts
Son of Sparky
by HotLine1
Yesterday at 07:43 PM
Speaking of Plugmold ...
by gfretwell
10/17/16 02:37 PM
Broken battery charger? Check for cobwebs!
by gfretwell
10/17/16 02:30 PM
230 or 345 kV transmission lines?
by annemarie1
10/12/16 01:23 PM
Is this a fix or just a bandaid?
by gfretwell
10/10/16 06:49 PM
New in the Gallery:
12.5A through 0.75mm flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 11
renosteinke 6
HotLine1 6
ghost307 5
Potseal 4
Who's Online
1 registered (HotLine1), 241 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#92395 - 03/15/05 10:57 AM Main Disconnect
InspectorE Offline

Registered: 10/08/04
Posts: 51
Loc: Hudson WI USA
Situation: Home plus agricultural building, current service is 200 amp.

The service line comes into a central point which is a generator shed (that's where the meter is). There is currently a 200 amp disconnect at the shed. Originally, the 200 amp was to feed both the house and the pole barn but now it is desired to upgrade to 300 amp service so the pole barn can have it's own 100 amp capacity leaving the full 200 amps for the home.

Can I just add a second 100 amp disconnect switch for the separate pole barn, or must I purchase a 300 amp disconnect so both buildings can be disconnected with a single switch? I realize a new meter socket will be necessary. I can't find anything specific in the code, but it may be inferred by a few sections.


2014 / 2011 NEC & Related Books and Study Guides
#92396 - 03/15/05 04:57 PM Re: Main Disconnect
earlydean Offline

Registered: 12/22/03
Posts: 749
Loc: Griswold, CT, USA
It is OK to just add a 100 amp disconnect for the shed. You are allowed up to six disconnects per service (230.71). The riser or lateral (and the meter enclosure) would need to be adequate for 300 amps if the load calculations warranted it, but, you could then tap off to each disconnect with 200 amp and 100 amp taps for the two buildings. What feeds the shed?

By the way, each building needs its own disconnect.

2002 NEC:
"VI. Service Equipment — Disconnecting Means
230.70 General.
Means shall be provided to disconnect all
conductors in a building or other structure from the service entrance conductors.
(A) Location. The service disconnecting means shall be installed in accordance with 230.70(A)(1), (2), and (3).
(1) Readily Accessible Location. The service disconnecting means shall be installed at a readily accessible location either outside of a building or structure or inside nearest the point of entrance of the service conductors."

I infer from your description that the service conductors stop at the shed, and feeders will feed each building.

"225.31 Disconnecting Means.
Means shall be provided for disconnecting all ungrounded conductors that supply or pass through the building or structure.
225.32 Location.
The disconnecting means shall be installed either inside or outside of the building or structure served or where the conductors pass through the building or structure. The disconnecting means shall be at a readily accessible location nearest the point of entrance of the conductors."

How close is that generator shed? Sounds like you need additional disconnects at each building.


ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals