Terminology

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Little Bill

Little Bill

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What is the difference between a bolted fault and a dead short?

Also how much wood could a ...............................characters needed.............
 
As I was TAUGHT, “Bolted Fault” is a theoretical concept wherein the fault has zero impedance /resistance. In testing of equipment for example, short circuit withstand tracings are done by literally bolting the output terminals together (these are fun to witness by the way, I’ve done so several times).

As I LEARNED later in real life, there is no official definition of “bolted fault”; it’s just a commonly used industry term (although it is used in NFPA 70E without definition I believe). Outside of the test lab, there is always some impedance and/or resistance in a fault. So by TESTING to a bolted fault condition, you are always testing to a worst case scenario that the equipment will never actually see in the real world.
 
Jraef said:
As I was TAUGHT, “Bolted Fault” is a theoretical concept wherein the fault has zero impedance /resistance. In testing of equipment for example, short circuit withstand tracings are done by literally bolting the output terminals together (these are fun to witness by the way, I’ve done so several times).

As I LEARNED later in real life, there is no official definition of “bolted fault”; it’s just a commonly used industry term (although it is used in NFPA 70E without definition I believe). Outside of the test lab, there is always some impedance and/or resistance in a fault. So by TESTING to a bolted fault condition, you are always testing to a worst case scenario that the equipment will never actually see in the real world.
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Bolted faults do occur in the real world. I have seen L1 and L2 conductors bolted to the same busbar.

Basically a bolted fault is an installation error. Effectively no arcing occurs during a bolted fault.
All other faults are incidental contact, like a loose or broken connection. Arcing is associated with non-bolted faults.
 
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