0 members (),
408
guests, and
18
robots. |
Key:
Admin,
Global Mod,
Mod
|
|
|
Joined: Oct 2000
Posts: 5,392
OP
Member
|
iirc, the higher voltages are more likely to assume jacobs ladder http://www.repairfaq.org/sam/jacobs.htmthe article mentions > A person named F. Pashchen in 1889 published a law which sets out what has become known as Paschen's Law. He determined the relationship between breakdown voltage, the gap between two metal plates, and the pressure. With air as the gas, the minimum voltage is 327V, as shown in Fig. 5. The peak of a 120VAC sine wave is only 170V, and thus continuous low current arcing is, by a law of physics, not possible with copper-copper. Thus claims that a Combination AFCI will respond to arcing at a break in a conductor or a loose connection flies in the face of a law of physics. http://en.wikipedia.org/wiki/Paschen's_law Anything i could add would be assumption, since this is EE turf so Scott, please be kind & translate to english k? and workmanship? well i'd love that perfect world where licensure, inspections, maintanence issues, and all entities involved could be on the same page beam me up! ~S~
|
|
|
|
Joined: Apr 2002
Posts: 7,382 Likes: 7
Member
|
More reading to peak my interests.
Great subject, this topic.
|
|
|
|
Joined: Mar 2004
Posts: 814
Member
|
Dragging this post back to the top because of something that happened recently. Never before have I seen it. I was installing a chandelier on a house that was completed earlier, and the chandelier box was capped off for future use. Whoever trimmed the house stuck a 3 way in the switch box because it had a 14/3 and they thought it was a 3 way but actually it was ran to the chandelier box possibly for a future fan. Anyway not knowing it was a 3-way (Decora), I flip the switch down and climb up to open the box. As I reach into the pancake to fetch the wires I hear a faint crackling, then next thing I know it sounds like a Lincoln Buzz Box and suddenly the red wirenut bursts into flames. I'm trying to grab it with my linesmans and I'm blowing on it but it will not stop burning. Finally I manage to rip it off the conductors and fling it to the floor, where it makes a good burn mark. Whoever trimmed had capped the unstripped red conductor in with the grounding conductor, and the wirenut must have just cut in enough to make for a nice load without enough to trip the breaker (no arc fault). If I had not seen this with my own eyes I wouldn't have believed it. That wirenut would not estinguish for anything. I think of this now everytime I see a flying splice in the attic.
|
|
|
|
Joined: Oct 2000
Posts: 5,392
OP
Member
|
Elevate that sentiment to a number of aging connections BigB That most have to 'glow' before they 'arc', and that a glowing connection can achieve incendiary temps has been an established fact for some time ~S~
|
|
|
|
Joined: Oct 2000
Posts: 5,392
OP
Member
|
Last edited by sparky; 11/07/13 10:56 AM.
|
|
|
|
Joined: Aug 2008
Posts: 62
Member
|
|
|
|
|
Joined: Apr 2002
Posts: 7,382 Likes: 7
Member
|
Good day Andey!
Is the pic from the mfg?
That looks like an extreemly neat j-box. Do you have any info on the listings of these? And cost?
John
|
|
|
|
Joined: Jan 2005
Posts: 5,445 Likes: 3
Cat Servant Member
|
Those are nothing more, or less, than Wago connectors. The real thing - not the Ideal clone. Yes, they're listed; box is marked. There's even a version with little levers that let you remove individual wires at will.
|
|
|
|
Joined: Jun 2004
Posts: 1,273
Member
|
The main utility for AFCI logic is to trip out when a worn commutator kicks up a fuss.
%%%
The hot spots of normal travail occur as localized heating -- like a spot welder.
BigB had me chuckling when he wrote of trying to blow an active plasma arc/ pinched conductor out with his breath.
I was also surprised that he assumed this or that wiring to be in place.
In EVERY residential structure, I always assume tha I can't assume anything. Homeowners/ home owers never step-up and admit that they've fiddled with the wiring... and will never give you an informed tale about what the Other Guy did the last time he had to crawl away from these circuits.
Lastly, three-ways control all of the chandeliers around my house. They're as common as dust for a fixture that typically is used to flood an entire zone. I simply expect to find three-ways.
What's weird is that that particular homeowner should've thrown the three-way long before he got there.
Then, hearing and smelling wrongful things, that very homeowner should've turned off the naughty switch and called a professional over to clean up their own handiwork.
%%%
Just take it to heart: you're being called in because the DIY gambit has gone astray. The damage has merely been throttled down -- awaiting your arrival.
Cheers.
Tesla
|
|
|
|
Joined: Jul 2004
Posts: 9,931 Likes: 34
Member
|
That "Surfen Tuben" (German version of ENT?) looks like interesting stuff too. Does it thread into the box?
Way cool.
Greg Fretwell
|
|
|
Posts: 57
Joined: August 2003
|
|
|
|