Powersave Posts

The Powersave posts remind me of something that happened at my previous employer about a decade ago. This guy contacted us wanting us to evaluate a
product he had invested in. He wanted some kind of letter of recommendation from us. He brought his product over (I won't post the name - although they are still on the market) for us to evaluate. It was a typical metal box that saved energy and made motors run cooler. He first demonstrated it using the "tools" he had been provided by the company. We, of course, pulled out real test equipment. It took about 5 minutes to figure out that what he had was a metal box full of capacitors. The real funny thing was that when he plugged it in one outlet, the votlage distorted horribly. The cap was acting as a third harmonic filter and was drawing huge third harmonic currents.
In a panic he called the company to have them explain the harmonics (we knew the problem). Once they told him there was nothing in the box but caps you could see the guy's whole world dissolving. After the call, he nearly cried. He had invested his entire life savings in an "exclusive residential marketing rights" in a certain area of the US. The problem, no real market for kvar correction on residential customers since the meter only measures kWh plus the fact that installing a cap at the meter does little or nothing to reduce the losses in the residence.
We felt sorry for the guy.
Charles Perry P.E.
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That sucks. These scam artists really deserve a hot place in hell.
CS
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On 9/16/07 5:11 PM, in article snipped-for-privacy@mid.individual.net, "Charles

I must be missing something. How do capacitors draw high third harmonic currents? Were they series tuned to the third harmonic? Even so, there would be little third harmonic current if there were not something nonlinear to produce a third harmonic voltage.
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wrote:

The addition of the capacitors created the resonance. Any time you add a capacitor to a power system, you create a resonance at some frequency. If you are unlucky, you create one at a point where there is a source of energy at that frequency.
As for a source of thirds, it was in a building housing a few hundred computers.
Charles Perry P.E.
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Charles Perry wrote:

What was the configuration of the caps in the gizmo? Series or parallel?
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Paul Hovnanian mailto: snipped-for-privacy@Hovnanian.com
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They were shunt. Phase to neutral.
Charles Perry P.E.
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Charles Perry wrote:

Ouch. :-(
But, think about it: The _right_ powersave devices *must* work. How else would those people in Nigeria have all that money they want you to help them get out of the country?
Ed
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