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View Full Version : Why doesn't a bulb s/c ?


dx4530
Jun 18, 2012, 10:13 PM
If the correct explanation of a short circuit is that when theirs a very low resistance conductor in the circuit then why doesn't the regular incandescent light bulb create a short ?

hfcarson
Jun 19, 2012, 03:58 AM
dx4530: It's all in the math and the physics...
a 60 watt lamp has a resistance of ~240 ohms so it draws about 1/2 an ampere... P=I^2 x R
If you Google the definition you'll find a few, mostly similar.
The definition of a short circuit, IMO, should include the description of a circuit
where an unintended connection occurs before the intended load...

A short circuit in a residential environment for example, with a 50 kVA transformer mounted on the pole may allow as much as 12,000 amperes of current to flow in what is called a phase to phase bolted fault or short circuit... This is deadly, ask any squirrel!