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*To*: tesla@xxxxxxxxxx*Subject*: Re: Current Limiting and Impedence*From*: "Tesla list" <tesla@xxxxxxxxxx>*Date*: Thu, 28 Apr 2005 10:48:20 -0600*Delivered-to*: testla@pupman.com*Delivered-to*: tesla@pupman.com*Old-return-path*: <teslalist@twfpowerelectronics.com>*Resent-date*: Thu, 28 Apr 2005 10:51:51 -0600 (MDT)*Resent-from*: tesla@xxxxxxxxxx*Resent-message-id*: <UUlOQC.A.LvF.lSRcCB@poodle>*Resent-sender*: tesla-request@xxxxxxxxxx

Original poster: "Paul B. Brodie" <pbbrodie@xxxxxxxxxxxxx>

Please excuse the intrusion. I am following this thread with great interest. When you say you are measuring the "voltage between the inductor and transformer," where are you attaching the voltmeter? I am having trouble understanding what you mean by between. Thanks for any clarification.

Paul

Think Positive

----- Original Message ----- From: "Tesla list" <<mailto:tesla@xxxxxxxxxx>tesla@xxxxxxxxxx> To: <<mailto:tesla@xxxxxxxxxx>tesla@xxxxxxxxxx> Sent: Wednesday, April 27, 2005 1:00 PM Subject: Re: Current Limiting and Impedence

>

>

> Gerry:

>

> Thanks for all your help. Now if you can bear with me and help me solve

> the original problem with the math(BTW <> is "not equal to")....

>

> I have (2) inductors in series. My current limiter and my transformer.

> Mains is 120V/60 Hz/1 ph.

>

> The current limiter is 15 mH, X = 5.65 Ohms, R = 0.3 Ohms.

> The transformer is Z = 1.2 Ohms, R = 0.3 Ohms, so X = 1.16 Ohms

>

> So System Impedence Z = 6.82 Ohms

>

> This gives I = 120/6.82 = 17.6 Amps and is near exactly what I am

> getting.

>

> The measured voltage between the inductor and transformer is about 90 to

> 95 volts. Have gotten as high a 100 volts. This is the voltage drop

> across the transformer. This is inconsistent with the above values and

> in fact seems reversed from what the math suggests. I have double

> checked it.

>

> For more confusion, lets compute power:

>

> True power = R*I^2 = 0.6*17.6^2 = 186 watts

> Reactive power = X*I^2 = 6.81*17.6^2 = 2109 var

> Apparent power = 2117 VA

> Power Factor: 186/2117 = .08 (makes no sense)

>

> I know I have 120*17.6 = 2112 VA input and approx 7500*.2=1500 watts

> output from the transformer secondary. Thus I have a power factor of

> approximately .71. I get 48 to 60" sparks from the coil/toroid so I've

> got to have near that kind of power.

>

> I believe that I am improperly accounting for the power that is

> transferred from transformer primary to secondary in the above

> equations. It's as if some of the reactive power "created" by the X of

> the inductor is actually true power for the transformer.

>

> I tested the current limiter and don't think it is saturating.

> (BTW - I'm a "math guy" so I can handle the vector addition and complex

> variables no problem. But struggling with setting up equations and how

> to apply them.)

>

> Thanks again for your help.

> Mark

>

>

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