Short Circuit / Fault Analogy 1

[enverd]

If someone would ask you to explain (dummify) what happens in a distribution circuit during a fault, how would you explain it to them?

For a lot of people, it is very important to have certain concepts like faults broken down to simple terms using analogies, so please share your understanding using basic language.

Thanks,

 

[DTR2011]

Magic Smoke makes everything electrical work...

 

[enverd]

smallgreek, I am stomped, I don't know what to say, why didn't I think come up with that?

Thanks,

 

[itsmoked]

The energy flow, instead of being limited by how much all the loads are able to use, changes to being limited only by what the entire system can supply. This usually means how much the smallest transformer in the circuit can pass. Hopefully a fuse or circuit breaker will 'protect' the systems from time accumulating damage.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Linspire]

What does magic smoke mean ?

 

[LiteYear]

The old water hose analogy works pretty well (up to a point of course).

Before the fault the tap (power station/transformer) is on and all the sprinklers (loads) are happily working away. A mower hits the hose somewhere creating a slice (fault) and a heap of water rushes through the slice, limited to what the tap (transformer) can force through the hose (series impedance). The pressure (voltage) in the system falls while the water flow (current) between the tap and slice is near its maximum. If the hose can be pinched shut (breaker opens) just upstream of the slice, only the sprinklers (loads) downstream of the breaker will be affected.

 

[davidbeach]

Magic Smoke. Don't even need the "Magic".

The smoke theory of electricity states that electricity is smoke contained within the wire. Everything works well as long as the smoke stays within the wires, but anytime the smoke gets out of the wires, things stop working. Anytime you see something electrical letting the smoke out, you can be pretty sure that it won't work any more.

 

[enverd]

Thank you all for the help.

Liteyear it seems like there a multiple instances where you can use the water analogy to explain electric theroy.

Thanks again.

 

[HornTootinEE]

Water is great for basics, just don't let the "non-believers" think it's always as simple as pressure and flow.

 

[jghrist]

Water may be great for basics, but to explain reactive power, you definitely need beer.

 

[enverd]

jghrist, I totally agree with you.
Have you thought about an how to include the beer (reactive) power into the analogy?

 

[jraef]

Here's a water analogy haiku for SOME aspects of a short circuit (suspend your physics for a moment).


High pressure in clay pipe.

Against it man crashes car.

Widow and children crying.


"Will work for salami"

 

[jghrist]

Have you thought about an how to include the beer (reactive) power into the analogy?

Search this forum for beer and reactive to get many threads such as thread238-255835

 

[DRWeig]

If you need a visual aid, light up a small lamp with a 9V battery - useful work, no short circuit. Fluff up a pad of steel wool until it's twice the size of the original. Stick the battery terminals into the wool. Illustration is a short circuit involving many small strands of wire. Fun! Even more effective in the dark.

Wear leather gloves. Do not wear polyester, nylon, or other meltable / flammable clothing. Keep a bucket of water or a fire extinguisher nearby. Eye protection required, full-face shield eve better. Non-flammable place to set the wool on before applying battery. Well-ventilated room or outdoors. An OSHA guy would require me to be in a welder's leather apron.

In other words, BE SAFE! Consider the temperature needed to melt steel. You'll be doing a lot of it.

Best to you,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies

 

[PHovnanian]

Hang on a sec. I'm working on a beer-foam analogy. So if someone asks me, I'll have an explanation ready, conditional on them buying the beer, of course.

 

[enverd]

#phovnanian,

I'll buy the first round, that is not a problem