Is the term "Short Circuit" undefined?

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Originally Posted by iwire
Given that definition there is no such thing as a short circuit.
All circuits 'short' or not have resistance.
My apologies,I misread your response, I thought it said "All circuits 'short' do not have resistance." (Hey, I'm getting old!)
 
Thank you everyone for the replies

Thank you everyone for the replies

In school, I learned the following definitions:

Ground fault: An unintended connection between phase and ground. Ground being, in turn, defined as earth, an equipment grounding conductor, metallic enclosures, etc. That is, between phase and any non-current carrying conductor. This is the definition of 250.2

Short circuit: An unintended phase to phase connection.

These two types of faults have different characteristics in almost every aspect and this is why they warrant a definition. It is sad that the NEC, uses the term "short circuit" loosely given that it is one of the most dangerous aspects of the electrical trade. I, again, think that they should include a definition on the next issue.
Thanks again
 
izak said:
hmm... whats a bolted fault?

Take two 1/4x4 inch copper buss bars tied into a 24 V power source capable of say 40,000 amps; now bolt another piece of copper to one of them with other end hanging loose by the other buss. Turn on power and bolt the other end to other buss. The results of this bolted fault will be your fault, of course you probably won't be able to discuss the fault. :p
 
Izak:
A bolted fault is one that is which the wires or whatever is causing the fault are directly connected. For example, when a transmission cable falls on top of, say, a transformer. The transformer's housing would probably not melt but, instead, it would conduct current through a breaker. Even though the circuit breaker can stop current flow, the fault still exists and it will conduct again whenever power is restored (As if the cable was actually bolted on to the transformer's enclosure).
 
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