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Electromagnetic Surge on Conductor

12/01/2014 10:19 AM

Hi guys, consider the figure above, a wire conductor with length "a-c" was exposed to an ElecroMagnetic Pulse in either direction (CW, CCW).

What are the corresponding Voltage Potentials at terminals "c & d" and "a & b" at that same instant?

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#1

Re: Electromagnetic Surge On Conductor

12/01/2014 11:15 AM

The voltage potential is the same at both ends making the assumption that the wire and ground are perfect conductors, which blows the whole thing out of the water anyway.

Homework problems like this frequently do not represent the real world.

The voltage is going to be expressed as a function of the magnetic field strength at the wire. Read your text book and do your own homework.

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#2
In reply to #1

Re: Electromagnetic Surge On Conductor

12/01/2014 11:20 AM

You have nothing to brag about, if you can't answer correctly.

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#3
In reply to #2

Re: Electromagnetic Surge On Conductor

12/01/2014 12:51 PM

You have an odd way of asking others to do your homework for you.

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#6
In reply to #2

Re: Electromagnetic Surge On Conductor

12/01/2014 5:02 PM

It is not a question of bragging or even answering correctly. We simply refuse to do other people's homework because it is a disservice to those who ask.

Your attitude will get you barred from this site if you continue to exercise bad manners. If you let your ego run your mouth in the real world, you are doomed to experience a lot of unemployment.

For your own sake, you need to read up on Etiquette because you are rude. This decade and the last will be remembered as the age of behavior. It seems that we tolerate gay marriages but we don't tolerate bad behavior.

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#8
In reply to #6

Re: Electromagnetic Surge On Conductor

12/01/2014 5:26 PM

Nope this not an assignment. This is posted in discussion.

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#4

Re: Electromagnetic Surge On Conductor

12/01/2014 12:57 PM

An electric field pulse would cause a->b and c->d to be in phase. A magnetic pulse would cause a->b and c->d to be in opposite phase. It depends on the conditions like the orientation of the pulse and the size and geometry of the conductors, and most likely they would be neither in phase nor of opposite phase but would be different waveforms.

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#5

Re: Electromagnetic Surge On Conductor

12/01/2014 1:24 PM

Rixter is right. It depends upon the length of the conductor, the size, shape and strength of the electrical or magnetic field. If the fields are changing that brings up a whole other set of calculations, dv/dt, di/dt, etc.

Noudge, this looks like homework, but you've been around long enough to make it unlikely. Can you explain why you're asking?

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#7
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Re: Electromagnetic Surge On Conductor

12/01/2014 5:23 PM

Good job Rixter as he/she figure it out with precision. You got my GA.

Just want to show "Anons" who was very interested how would they treat lightning surge I want to show them the concept. Protection in one end line of a wire conductor (like only the mains) still does not guarantee safe to other ends connected devices.

So if you want to protect wires and all your devices, SPD's are required at both ends of the wire.

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#9
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Re: Electromagnetic Surge On Conductor

12/01/2014 6:24 PM

Nonsense. A surge arrester can never give you assured protection against lightning strikes.

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#10

Re: Electromagnetic Surge on Conductor

12/02/2014 8:54 AM

As postulated, the potential relative to ground at points a and c are zero just before the pulse is applied therefore they are zero at the instant the pulse is applied since nothing in nature changes in zero time. The pulse then splits and travels at the speed of propagation along the conductor in both directions at the same rate until it reaches points a and c, at which time the voltage appears with a fast rise-time. Since this is an unterminated transmission line the pulse will be reflected back to its origin and the cycle repeats until all the energy dissipates. Of course the same is true for the pulse traveling in the opposite direction. Transient analysis is different than steady state analysis.

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Anonymous Poster (1); Crabtree (1); Lo_Volt (1); NotUrOrdinaryJoe (2); Noudge79 (3); RAMConsult (1); Rixter (1)

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