ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
May I backfeed 3 phase transformer?
by dsk - 10/22/21 04:37 AM
Wire sizing
by gfretwell - 10/21/21 10:12 PM
GFCI's pops in large numbers
by dsk - 10/21/21 02:03 AM
Need some info on Japanese outlets, 200V 15A
by andey - 10/20/21 08:05 AM
nec 110.3 (B)
by watersparkfalls - 10/19/21 07:09 AM
New in the Gallery:
240/208 to a house
240/208 to a house
by wa2ise, October 9
Now you know.
Now you know.
by Tom_Horne, September 7
Who's Online Now
0 members (), 11 guests, and 18 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#92395 03/15/05 02:57 PM
Joined: Oct 2004
Posts: 53
I
Member
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.

Thanks!

2017 / 2014 NEC & Related Books and Study Guides
#92396 03/15/05 08:57 PM
Joined: Dec 2003
Posts: 751
E
Member
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.


Earl

Link Copied to Clipboard
Featured:

Tools for Electricians
Tools for Electricians
 

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
togol
togol
NW In. USA
Posts: 421
Joined: September 2005
Top Posters(30 Days)
dsk 7
Popular Topics(Views)
284,754 Are you busy
217,367 Re: Forum
203,709 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5