# Re: How should we measure coil efficiency

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From: 	John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
Sent: 	Thursday, July 24, 1997 12:17 PM
To: 	Tesla List
Subject: 	RE: How should we measure coil efficiency

At 04:56 PM 7/24/97 +0000, you wrote:
>
>From: 	Greg Leyh[SMTP:lod-at-pacbell-dot-net]
>Sent: 	Wednesday, July 23, 1997 5:17 PM
>To: 	Tesla List
>Subject: 	Re: How should we measure coil efficiency
>
>John H. Couture wrote:
>
>
>>  John, Greg, All -
>>
>>  The Tesla coil efficiency is found with the following equation:
>>
>>          % eff = (energy out/energy in) x 100
>
>
>Isn't that what I meant when I stated:
>Energy in Csec = (energy in Cpri) X (coil efficiency)  ??
>
>
>>   Note that energy equals watts x time. Measuring the "energy in" is
>> possible by measuring the watts x time at the input.
>
>So, you no like  Epri X BPS = watts in?
>This seems like a much easier msmt to me, and more accurate.
>
>
>-GL
>
>----------------------------------------------

Greg -

I agreed with your eff equation. To find the "energy in Cpri" you need to
know how much the Cpri voltage actually is after the charging. I believe
this can only be done with a single charge using a DC Tesla coil. Did you
meam a DC coil?

The "watts in" with Epri x BPS could be used with DC Tesla coils.

Tesla did use "total watts in" divided by BPS in the CSNotes. I would
agree to this method. As I recall he got about 4 watt sec per foot of spark.
Coilers do not use this method today.

JHC
>
>
>

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