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Anonymous Poster #1

Voltage Increase at the Induction

08/19/2012 11:57 AM

Why there is many times voltage pick at an induction after the supply to it get interrupted ?

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#1

Re: voltage increase at the induction

08/19/2012 12:06 PM
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Anonymous Poster #1
#2

Re: voltage increase at the induction

08/19/2012 12:09 PM

Better to put my qwestion so:

Why instantaneous voltage rise on an disconnected coil can exceed many times the nominal supply level ?

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#3

Re: voltage increase at the induction

08/19/2012 12:20 PM

Why not make it easy on us all?

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#4

Re: Voltage Increase at the Induction

08/19/2012 8:45 PM

dI/dt.

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#5
In reply to #4

Re: Voltage Increase at the Induction

08/19/2012 8:51 PM

That, too.

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#6

Re: Voltage Increase at the Induction

08/20/2012 11:13 AM

In the text book under inductors you will find an equation for voltage that looks like this: v=di/dt

This says that the voltage on the inductor = rate of change of the current.

So if the current was flowing along, just minding its business and you come along and change it by disconnecting it, the rate of change is very very small.

Now, what happens when you divide by something very very close to zero?

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Anonymous Poster #1
#7
In reply to #6

Re: Voltage Increase at the Induction

08/20/2012 2:48 PM

So, it is also true for an active load too ?

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#9
In reply to #7

Re: Voltage Increase at the Induction

08/21/2012 6:23 AM

#8↓ is true for all loads.

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Anonymous Poster #2
#8
In reply to #6

Re: Voltage Increase at the Induction

08/21/2012 6:22 AM

V=di/dt

V=L.di/dt

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Anonymous Poster #1
#10

Re: Voltage Increase at the Induction

08/21/2012 1:47 PM

Thanks ! - now I am aware of this.

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