3 Jul
2004
3 Jul
'04
8:06 a.m.
If I had to do such a "deliberate trip"
today, I'd probably do
something like plug in an iron and a hair dryer - high-draw devices
that together exceed the breaker's trip point, but not as drastically
so as a dead short.
The trouble with that is most non-electronic breakers need 100%
overcurrent to trip in <15 seconds, so it would take five 1500W
hair dryers to trip a 15A circuit.
This makes testing 100A three phase breakers interesting.
Lee.
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3 Jul
3 Jul
9:28 p.m.
The trouble with that is most non-electronic breakers
need 100%
overcurrent to trip in <15 seconds, so it would take five 1500W hair
dryers to trip a 15A circuit.
At 120V, 1500W is 12.5A (assuming a purely resistive load, which for a
hair dryer is slightly inaccurate but not enough so to worry about).
100% overcurrent on a 15A circuit is 30A. 30/12.5 = 2.4. Where did
you get "five"? Are you thinking European mains voltage maybe? Since
I'm in North America, it's unlikely I'd be working with 240V.
This makes testing 100A three phase breakers
interesting.
Well, yes. That is the sort of circumstance that made me add
"probably" to my comment - I am unlikely to be working on such
equipment. :-)
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