I’d really love to see a cite for that…
[I feel like the FQ OP was answered (?)]
Oh, excellent choice!.
That doesn’t really make sense. First of all, a circuit breaker is designed to be reset and continue to be functional after the downstream problem is fixed. Secondly, If a circuit breaker trips, your first assumption should be that it is working properly, and something made it trip. The circuit breaker should only be replaced when a downstream problem can’t be found, and hence you suspect the breaker itself is the culprit.
My house in Chicago had a fuse box instead of circuit breakers (I had once considered having it changed over but the expense was out of my budget. One of the first things I did after I moved in was verify exactly what each fuse was connected to. This involved having someone in the basement with a walkie-talkie (this was in the days before cell phone) who would remove a fuse while someone else went through the house checking what no longer had power - appliances, lights, outlets, etc. We then posted an accurate listing near the fusebox for future reference.
At some point later I had a problem with a particular fuse that kept blowing. After some checking I figured out that the chest freezer, the microwave, and a portable dishwasher (among, i think some lights) were all on that fuse. What was causing the fuse to blow was that if we ran the dishwasher and the microwave at the same time, every so often the chest freezer would also cycle on, causing the fuse to blow. So from then on we never used the dishwasher and the microwave at the same time, and the fuse stopped blowing.
I tracked down the source and have asked; he says he’ll hunt it down. And it was TWO overload trips, not one, so I had that slightly wrong. Though how you’re supposed to keep track of TWO is an interesting question. If this is universal, you’d think there would be a break-off tab or something that you’d remove the first time, so when the second one happens years later, you’d know.
I had a similar problem in a prior residence where they’d upgraded the kitchen all Cheap Charlie.
Had a row of outlets hidden on the underside of the cabinets in the rear. With a toaster, microwave, & coffeemaker plugged in.
Two out of three was OK. but if the coffeemaker was still boiling water, not just keeping the pot’s hot plate warm, and you activated the other two … CLICK!! Crap!
I pit installers/electricians/technicians who don’t check the breakers after the installation.
But apart from that, it’s Tuesday night? What happened?
By the way, there are a couple of well-known switch brands in Aus, with different wiring patterns. If I take a wall switch out of my home, and replace it with something cheaper, by default I’ll connect active to earth, instead of connecting active-to-switched-pole. I have to check and re-order the wires for the new wire pattern.
According to Trippin’ How many times can a breaker trip? citing the UL489 standard for circuit breakers, there is a two-trip count that exists. Specifically, a circuit breaker must be able to successfully interrupt an overload of whatever current it claims as its maximum ability to interrupt, at least twice. Branch circuit breakers are usually rated to be able to interrupt 10,000A or 22,000A. Interrupting that much current certainly could start to damage the internal contacts.
Most “routine” trips will not be anywhere near the interupting-limit. Plugging too many space heaters in to a 15A or 20A receptacle circuit might overload by a single-digit multiple, generally well under 100A. A stalled motor will draw many times its rated current, but again nowhere near that limit - the inherent resistance of the windings limit the maximum possible current.
A circuit breaker needing to clear a fault at its limit should be exceedingly rare, and occur only under very specific conditions. The utility transformer would have to be able to supply that much current, there can’t be too many other loads on it, the fault must be very low-resistance, and the resistance of all the wiring between the transformer and the fault must be sufficiently low.
As an example, a 25’ #14 cable (50’ round-trip distance) with the hot and neutral wire-nutted together has a resistance of 0.12625 Ohms and on a 120V circuit cannot pass more than 950A (and in reality will be lower due to other resistance in the circuit). A 25’ cable of #10 (again 50’ round-trip) is 0.049945 Ohms with an absolute maximum of 4800A on a 240V circuit.
So maybe my source was (mis?)interpreting this? Not sure it fully answers the question, but it’s definitely getting us closer! I’m’a send this to him, see if he says “Yeah, that’s it”, in which case I can say “But that’s not quite what you said…”
Reading from the OP, it occurs to me that they report finding the breaker in the OFF position. Unless the installer placed it in the OFF position and neglected to turn it back on, I’m inclined to suspect that the breaker was found in (what I have been conditioned to call) a “trip-free” position, and that any attempts to turn it back on without definitively setting it to to real OFF position were invalid, and did not “count,” so to speak.
The OP should be able to safely set the breaker to OFF and reset the breaker once. Keeping in mind that breakers do not typically trip on a whim, and there could be an underlying issue (possibly an internal wiring error in the newly-installed appliance.
DISCLAIMER: I am not a licensed (or trained) electrician.
NB: I have encountered breakers that are not famous for making the “trip-free” and OFF positions easily discernible.
ETA: This thread is a few days old. Has there been a resolution?
(Missed the edit window)
NO. IME, the only possible conditions are “trip free” or successfully connected.
If so, the solution should be posted and the thread closed.
This was my assumption as well, and alluded to that in when I asked a question above. I don’t think the breaker ever got reset.
The OP comes back to the thread and refers to the Tripped position:
And a bunch of posters commented on how it likely wasn’t Off but Tripped.
And the problem is, if you try to set a breaker back to the On position from Tripped, it just goes back to Tripped, not because there’s still a fault somewhere in the circuit, but because you didn’t reset it to Off before setting it back to On.
Eh, some of the new “spark detection” breakers will trip whenever you attempt to plug in an old electric motor. Like a vacuum cleaner or power tool. Because if any of the bristles on the metal brush that spins have worn down they create a tiny spark with each rotation. That feels like a whim when it happens to you.
Supposedly the newer algorithms can recognize the “normal” waveform signatures produced by brushes & commutators, and not trip when they’re encountered. Not sure how well they perform in real-world situations, though.
I know of a couple homeowners who have gotten so sick and tired of nuisance trips from AFCBs that they replaced them w/ traditional breakers. (Disclaimer: I am not suggesting you or anyone else do this, though.)
One would think that modern microcontrollers could be programmed to ignore a small arc that appears at multiples of 60Hz…
After failing to run the cleaning lady’s vacuum cleaner or any of the floor guy’s tools, i replaced some of my fancy new breakers with old ones. They are less safe than the new ones. They also let me use power tools in the workshop.
I’ve had problems with sparky, motory devices tripping ground fault circuit interrupters which ‘break open’ for reasons other than overcurrent. Doubly annoying since, unlike a breaker or fuse, I know there isn’t really a safety problem but I still have to go push the button to resume.
Edit: reply intended for continued discussion, no OP
The OP said the breaker was for a water heater, so is should be a plain vanilla breaker - no GFCI, no arc fault.