On Sep 2, 2011, at 12:54 PM, Alan J Fletcher wrote:
At 01:04 PM 9/2/2011, Horace Heffner wrote:
[snip]
Gee, if choppers are used this creates transients in the input,
and invalidates the use of ordinary current meters or power meters.
The current meters in the experiments were on the mains-side of
the control box.
Yes, I was very familiar with this. I watched the video. Rossi
used a clamp on AC ammeter, clamped around a wire exposed by cutting
into the power cord insulation.
My point is choppers put significant current and voltage transients
on the input (and output) power supply lines. The adverse effect of
erratic pulsed signals on rms current and power measurement has been
discussed since the days of Fleischmann and Pons. Using rms current
and voltage to compute power then results in a power that is way too
low. A fast integrating power meter, such as the Clarke-Hess
wattmeters is required for accurate power and total energy
measurements. See:
http://www.clarke-hess.com/
http://www.clarke-hess.com/chinfo.html
The only way reasonable power measurement is likely to occur without
a fast integrating watt meter is if there is an adequate filter
between the meter and the blue box. Same goes for output leads.
Being able to plot cumulative energy in vs cumulative energy out is
very important to "excess" thermal energy experiments, especially if
instabilities are involved, or in-run thermal pulses are used to
validate calibration.
The difficulty with transients on input power lines is that they skew
the results in the direction of apparent (false) excess power.
Therefore they can not be ignored.
It is also notable that if the neutral and ground are shorted
together in the blue box, and the ammeter is clamped on the neutral,
that input power estimates could be double that estimated.
There are good digital power plus kWh meters that can be had for
under $200. For example:
http://kwhmeters.com/EKM-23IDS-N_v.2.html
However, they need fairly smooth sinusoidal demand.
For 120 V operation a Kill-A-Watt brand meter can be obtained from
amazon.com for under $20. Not useful for Rossi, except maybe in the
USA, but I have found this to be a very useful meter. P3
International also has lots of other cool stuff:
http://www.p3international.com/products/index.html
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
