2850 watts didnt trip my 20amp breaker?

[JEDI]

4 slice toaster uses 1350 watts.
microwave uses 1500 watts.

I had both on the same time and they're on the same circuit.
microwave was at 100% power.
House was built in the early 1990s.

2850w/120volts = 23.75amps

So why didn't the breaker trip?


edit:
so I tested it again.
apparently my fridge is also on the same circuit.
toaster, microwave + 6amp fridge = tripped 20A breaker.

the 2nd 20A circuit in my kitchen only powers 1 duplex outlet on the counter (right of the sink).
nothing is ever plugged into it because there's not much counter space so my dish drying rack is there.

the one that tripped powers 3 duplex outlets AND the fridge (left of the sink).
stupid builders.

 

[pcgeek11]

It probably would eventually. The breakers isn't instant as the current calculated is on the edge.

Assuming a 20 ampere circuit breaker.

 

[Greenman]

I would assume appliance wattage is always measured at peak draw.

 

[JEDI]

I would assume appliance wattage is always measured at peak draw.

toaster = on isn't peak draw?
microwave = 100% power isn't peak draw?

 

[shabby]

My 2 slice toaster runs at 800 watts, just checked with a kill-a-watt.

 

[Greenman]

The only breakers I've ever herd of that will go way over rated amperage without tripping are Federal Pacific. An electrician I know tested one in a lab at the union school and they were able to pull a measured 50 amps through it before it tripped. That's probably why FP is out of business.

 

[pcgeek11]

How long did they run together?

 

[echo4747]

The only breakers I've ever herd of that will go way over rated amperage without tripping are Federal Pacific. An electrician I know tested one in a lab at the union school and they were able to pull a measured 50 amps through it before it tripped. That's probably why FP is out of business.

Yes.. Federal Pacific breakers are dangerous. Also the ITE Siemens Bulldog "Pushmatic" type breakers also get stiff when old and have a fairly high rate of failure too.

 

[Subyman]

The only breakers I've ever herd of that will go way over rated amperage without tripping are Federal Pacific. An electrician I know tested one in a lab at the union school and they were able to pull a measured 50 amps through it before it tripped. That's probably why FP is out of business.

Federal Pacific are horrible. Notorious for burning down houses. There was even a class action law suit. When I see them in the houses I do, I replace the entire thing, no questions asked.

I'd say the OP could post a pic of the panel and we'd be able to tell him if it is a safe set up. As others have said, breakers won't trip instantly. Might take a bit at the edge.

 

[Red Squirrel]

That's only 24 amps, it might take a few minutes before it trips depending on the trip curve of the breaker. Or it's a FPE Stab Lok.... read up on those.

Also did you actually measure what was being puled with a true RMS meter? I would not just go by the ratings of the appliances.

 

[DrPizza]

Did you have both sides of the toaster down? If you only had one side down, it wasn't using 1350 watts.

Also, we shouldn't assume that it's the breaker that's not operating according to the rating. It could be any of the appliances, the breaker, or a combination. Also, the fridge wouldn't be drawing 6 am

Counter top microwave? Built in microwaves are supposed to be on their own circuit. I also thought that the fridge was supposed to be on a separate circuit from the two required circuits for counter tops. Edit: I double-checked, I guess not, though a lot of people recommend it. 6 amps isn't a lot for a circuit, but there are so many appliances in kitchens with significant draw, that it can turn into a nuisance.

 

[Raizinman]

Is it not possible that the fridge or other plug outlet is on a different circuit protected by a separate breaker? Electricians know that kitchens use lots of electricity with mixers, toasters, griddles, etc.

 

[Jerem]

There are manufacturing tolerances. A toaster may or may not pull as much as the label says. Same goes for the microwave. Add in the possibility that line voltage was over or under 120 and who knows. Best thing is to get a clamp on ammeter and test at the breaker. Or, when in doubt, and considering the cheap easy replace these things are, replace it with a good quality breaker.