Forums | Home Repair | Home Improvement | Painting | Interior Decorating | Remodeling | Landscaping


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 10-18-2007, 12:03 PM   #16
Member
 
Join Date: Jun 2007
Posts: 3,502
Share |
Default

fuses to breakers


Andy, Sorry I did not think about the spaces available on the single phase panel. I was thinking NEC max.

The reason I like to leave the existing panel hot, while I work on the new one is flexibility.
Should I not finish before dark or if bad weather stops me, it will not leave the homeowner without power.

And I will not leave my generator behind.

Last edited by J. V.; 10-18-2007 at 12:05 PM. Reason: spelling
J. V. is offline   Reply With Quote
Old 10-18-2007, 05:07 PM   #17
UAW SKILLED TRADES
 
Stubbie's Avatar
 
Join Date: Jan 2007
Location: Kansas
Posts: 4,834
Default

fuses to breakers


Yes, 10KA would be generally greater than any available fault current that would be imposed on the load side terminals of the branch ocpd. The minimum fault current available is around 5000 amps. Our transformers are any range of kva to the point of being spec'd for a single residence if in a rural location. Just depends on how many dwelling loads are placed on it. Generally they are between 25 kva and 50 kva. I believe a 50 kva single phase transformer shows 14 kva as the available fault current but I would have to check that to be 100% certain. I'm reasonably sure this is a bolted fault at the secondary of the transformer.

Residential load centers are usually "series-rated" for a 22KA SCCR (short circuit current rating) main breaker/load center . This allows them to be installed with 10KA branch breakers.

Hope this answered your question
__________________
" One nice thing about the NEC articles ... you have lots of choices"

Stubbie
Stubbie is offline   Reply With Quote
Old 10-19-2007, 06:06 AM   #18
Once fried, twice shy.
 
elkangorito's Avatar
 
Join Date: Sep 2007
Location: Thailand
Posts: 251
Default

fuses to breakers


Quote:
Originally Posted by Stubbie View Post
Yes, 10KA would be generally greater than any available fault current that would be imposed on the load side terminals of the branch ocpd. The minimum fault current available is around 5000 amps. Our transformers are any range of kva to the point of being spec'd for a single residence if in a rural location. Just depends on how many dwelling loads are placed on it. Generally they are between 25 kva and 50 kva. I believe a 50 kva single phase transformer shows 14 kva as the available fault current but I would have to check that to be 100% certain. I'm reasonably sure this is a bolted fault at the secondary of the transformer.

Residential load centers are usually "series-rated" for a 22KA SCCR (short circuit current rating) main breaker/load center . This allows them to be installed with 10KA branch breakers.

Hope this answered your question

Thanks Stubbie. This absolutely answers my question .

I guess it shows the differences of our 2 systems. I believe in the old saying, "Better to be safe than sorry".

Cheers mate
__________________
Switchboard design engineer & Licensed Electrician (Australia).
elkangorito 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
Zinsco breaker boxes and breakers. evosounds Electrical 3 07-29-2007 06:08 PM
fuses to circuit breakers!! help!! ilovemyfamily Electrical 5 07-24-2007 07:01 PM
First time with old style fuses in fuse panel darsunt Electrical 3 06-20-2007 03:53 PM
HOT breakers, need advice.... Patriot_RAM Electrical 13 07-16-2006 10:39 PM
Adding new circuit breakers to 100 amp sub panel DrP Electrical 8 05-25-2006 10:05 PM




Top of Page | View New Posts

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