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 12-01-2006, 12:39 PM   #1
Newbie
 
Join Date: Nov 2006
Posts: 8
Share |
Default

breaker life expectancy??


In another forum, someone noted that the tensoin spring in most breakers will start to give at around 12 cycles (trips). I'd never really thought about this before, but does this square with the good folks here in the e- forum? It sure seems low to me. I've never had one trip 12x before, but I have cycled breakers numerous times while doing odds and ends work on circuits over the years, and never given one thought to maybe playing out the breaker. Do I need to rethink this?

thanks!
houser

houser is offline   Reply With Quote
Old 12-01-2006, 02:06 PM   #2
Electrical Contractor
 
jbfan's Avatar
 
Join Date: Jun 2004
Location: Newnan GA
Posts: 5,743
Default

breaker life expectancy??


I have never seen anything in the instructions that say a breaker will last X times of being turned on and off.
I think the other fourm is blowing smoke.

__________________
Yes I am a Pirate, 200 years too late. "Jimmy Buffett"
jbfan is online now   Reply With Quote
Old 12-01-2006, 05:10 PM   #3
World famous jerk.
 
Join Date: Dec 2005
Location: central PA
Posts: 440
Default

breaker life expectancy??


Even if the springs in the breaker did get weak after 12 trip cycles, that would present no hazard. The breaker would trip prematurely or nuisance trip. Don't sweat it. Large, commercial breakers have a special little button you're supposed to press on a scheduled interval to exercise the trip mechanism. If this was a real concern, it would be in published data from the manufacturers or in the UL book. It is in neither place. Sleep well.
mdshunk is offline   Reply With Quote
Old 12-02-2006, 12:05 AM   #4
Member
 
Join Date: Jul 2006
Posts: 120
Default

breaker life expectancy??


Two other questions if I may.

How does this affect the use of breaker of as switches? In my area this is commonly done in, for example, machine shops during off hours. I was told once that this was bad practice, but as I said it is common. I also have numerous peices of electrical equipment (mainly DC power supplies) for which use a breaker as the on/off switch, so presumably the manufactor wouldn't do this if there where a problem, but then they aren't using "normal" breakers, so maybe they are sepcially desgined for this.

I though large commercial breakers were a PITA to reset. I basically thought one had to have a special team come out and perform various equipment tests. We where once contemplating having a breaker (which was in readily accessible location) also serve as an emergency power switch, and were told that even in an emergency we weren't ever supposed to actuate them. (I was also under the impression that some of the really big breakers were ordinance actuated.)
LanterDan is offline   Reply With Quote
Old 12-02-2006, 09:39 AM   #5
World famous jerk.
 
Join Date: Dec 2005
Location: central PA
Posts: 440
Default

breaker life expectancy??


Quote:
Originally Posted by LanterDan View Post
How does this affect the use of breaker of as switches?
Breakers used as switches must be marked as "switch duty". It will have a the marking "SWD" on the breaker. Most branch circuit breakers nowadays are so marked.

[quote=LanterDan;25570] I though large commercial breakers were a PITA to reset. I basically thought one had to have a special team come out and perform various equipment tests. [/quote]
The reason for the "team" is to determine if a fault still exists before you reset the breaker. If you reset a very large breaker that tripped due to a bonafide fault, you could cause all hell to break loose. I have never heard of an ordinance actuated breaker, but they may exist someplace. I suspect the reason that this impression might exist is because some breakers say "ARMED" in a little window when the trip mechanism is fully cocked or fully wound. There are larger breakers that you need to pump a handle to cock the trip spring, and there are larger breakers that use a small motor to wind the trip spring.

There is required testing at certain intervals on all very large commercial breakers. These are breakers that cost in the 20,000 and up range when they are new. Insurance companies generally want them tested every few years. This is done on site, by companies that specialize in such testing.

Last edited by mdshunk; 12-02-2006 at 09:42 AM.
mdshunk 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
New GFCI Breaker Tripping w/ 3-way Flourescents BigJimmy Electrical 8 12-29-2008 02:29 PM
Circuit breaker panel - Advice needed justtired Electrical 15 12-13-2007 05:55 AM
Outdoor breaker panel questions lhoney2 Electrical 12 07-19-2007 05:44 PM
Breaker Buzz SkipI Electrical 2 07-13-2007 07:48 PM
Holy smoking commander breaker drogosandybanks Electrical 13 01-10-2007 02:34 PM




Top of Page | View New Posts

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