Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 09-02-2013, 01:45 PM   #1
Member
 
Join Date: Nov 2011
Posts: 128
Rewards Points: 75
Default

Is this a code violation?




This is an old Square-D split-bus panel type QO-20-4120, rated for 100 amps. House itself has 100 amp service at the meter. However, if you add up the ratings for the top 6 "disconnecting means" breakers, you end up with more than 100 amps. Theoretically, this setup could draw more than 100 amps.

Obviously, most split bus panels themselves are no longer legal (408.36 exception 1) but this panel would be grandfathered in I believe.


Last edited by kwilcox; 09-02-2013 at 02:00 PM.
kwilcox is offline   Reply With Quote
Old 09-02-2013, 01:59 PM   #2
Electrical Contractor
 
wirenut1110's Avatar
 
Join Date: Apr 2008
Location: Chester, VA.
Posts: 1,049
Rewards Points: 500
Send a message via AIM to wirenut1110
Default

Is this a code violation?


No, it's not a code violation. That is NEVER a way to figure the load on the panel.

Hell, if you add up the breakers that's on the 60 amp breaker feeding the lower half, it's more than 120 amps.

wirenut1110 is offline   Reply With Quote
Old 09-02-2013, 02:31 PM   #3
Member
 
Join Date: Nov 2011
Posts: 128
Rewards Points: 75
Default

Is this a code violation?


I like that answer and guessed that would be the case here.

What bugs me however, is that the lower breakers in the example you cite can't collectively draw more than the rating of the top breaker that protects their feeder. Not the case for the top 6 breakers which can collectively draw more than 100A.

What protects the meter base (rated for 100A) and the feeder from the base to the panel as well as the panel itself?

Last edited by kwilcox; 09-02-2013 at 02:33 PM.
kwilcox is offline   Reply With Quote
Old 09-02-2013, 02:41 PM   #4
Electrical Contractor
 
wirenut1110's Avatar
 
Join Date: Apr 2008
Location: Chester, VA.
Posts: 1,049
Rewards Points: 500
Send a message via AIM to wirenut1110
Default

Is this a code violation?


Nothing really 'cept the POCO's fuse, which ain't gonna happen...lol

Probably one of the reasons they're not allowed anymore but, I wouldn't worry about it.
wirenut1110 is offline   Reply With Quote
The Following User Says Thank You to wirenut1110 For This Useful Post:
kwilcox (09-02-2013)
Old 09-02-2013, 02:42 PM   #5
Licensed Electrical Cont.
 
Speedy Petey's Avatar
 
Join Date: Feb 2004
Location: NY State
Posts: 6,858
Rewards Points: 2,020
Default

Is this a code violation?


Quote:
Originally Posted by kwilcox View Post

What bugs me however, is that the lower breakers in the example you cite can't collectively draw more than the rating of the top breaker that protects their feeder. Not the case for the top 6 breakers which can collectively draw more than 100A.
Again, adding up the breakers is a completely meaningless number. You also have to consider, adding up 120V single-pole breakers is not any kind of comparison to the 240V feeder breaker at the top. To make that useless comparison you'd have to add up all the 120V breakers and divide them in half....which is totally not worth even doing.



Quote:
Originally Posted by kwilcox View Post
What protects the meter base (rated for 100A) and the feeder from the base to the panel as well as the panel itself?
Nothing. The breaker on the utility transformer really.
__________________
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.
Answers based on the 2008 & 2011 NEC.
Speedy Petey is offline   Reply With Quote
The Following User Says Thank You to Speedy Petey For This Useful Post:
kwilcox (09-02-2013)
Old 09-02-2013, 06:28 PM   #6
Member
 
Join Date: Nov 2011
Posts: 128
Rewards Points: 75
Default

Is this a code violation?


Thanks for the replies guys!

kwilcox is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Code violation? ovahimba Electrical 2 12-13-2010 10:13 AM
Carrier Error Code 33 russell124 HVAC 4 12-04-2010 07:19 PM
Canadian Electrical Code Question flemingetq Electrical 4 11-25-2010 09:42 AM
Distance between Heater & Combustibles DIY_JC Building & Construction 7 01-20-2009 07:52 AM
Building code violation fetzo Building & Construction 18 03-22-2008 02:42 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.