Re: LTR vs. STR for pigs was Re: PFC Question

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Malcolm Watts" <m.j.watts@xxxxxxxxxxxx>

Hi Steve,

On 18 Nov 2005, at 11:41, Tesla list wrote:

> Original poster: Steve Conner <steve@xxxxxxxxxxxx>
>
>  > flawed - that factor applies
>  > to *wallplug draw*
>
> I think Malcolm meant that he had assumed the BPS
> would be 100,

Right on that one. Subsequent scoping showed the breakrate to hit
twice the expected value quite often.

 and assumed some bang energy based on
> theory, and calculated the coil's power draw on the
> basis of that.

Not quite - I metered the gap setting with a DC EHT supply. The
possible fly-in-the-ointment with that one is that the gap voltage
*might* not have been that value or constant during repetitive
operation.

 However, AC charging coils can draw a
> lot more power than you would assume, because of
> resonant charging and ferroresonance effects. This is
> the "flaw" he mentioned.

Yes, and the transformer I used did indeed get hot pretty quickly. It
did have rather a lot of resistance in its secondary and the core was
operated in semi-saturation to boost the secondary voltage. Imag from
memory was about 5A.

Malcolm

> So if you want to have your claims on efficiency taken
> seriously, you have to actually measure the power
> going into your system from the wall plug, with a true
> RMS wattmeter. This is what is meant by "wallplug
> draw".
>
> You can get a digital power meter such as the Radio
> Shack Kill-A-Watt for about $20 nowadays. I tested one
> of these digital meters against an old-style
> mechanical wattmeter and they agreed well on a nasty
> rectifier and capacitor load.
>
> Steve Conner
> http://www.scopeboy.com/
>
>
>