Hi: Can you tell me how create an energy saver like this:
Thank you
Hi: Can you tell me how create an energy saver like this:
Thank you
You can buy one of these,
????? "use a *capacitor* ????? Lemme see...
1) Waste power to convert AC to DC. 2) Use capacitor to filter these spikes (some power wasted here as well). 3) Waste more energy to convert the DC back to AC. Did i miss something?? BW, nice looking vacuum cleaner...
Yep.
Yep.
Yep.
Don't need to do that, in fact it DOESN'T do that anyway. (because that would mean it actually DID something).
Yes, you forgot to mention the obvious, and say the magic word "scam".
Too small, it's slightly smaller than a pack of cigarettes.
That said, one box will cause you to (eventually) die of lung cancer, the other will cause suicide when you realise you've been scammed.
-- Linux Registered User # 302622
I don't know too much about PF correction but I do know:
Stove: Doesn't need power factor correction. Incandescent lights: Doesn't need PF correction. Vacuum: Who cares..not on long enough Computer: Already has PF correction.
Ballast for tube lights: ?? Let's say a ballast has a PF of 0.5. So 200Watts billed to supply 100Watts. (If I got that right..)
Does a 90% efficient converter doing power factor correction that burns 10Watts to deliver 100watts to a ballast result in a power reduction of 90 watts?
Fridge?
D from BC
Electric meters only bill for "real" watts, so one does not pay for extra amps due to poor power factor. Actually, one pays for watts lost in wiring downstream of the electric meter, but correcting power factor is unlikely to save more than a couple to occaisionally a few percent there.
Power factor is mainly of concern to commercial and industrial customers, since power companies do not want to install or add capacity to carry current that does not translate to billable watts.
Also, most fluorescent fixtures 32 watts or more already have high power factor.
Power factor of most induction motors is said to be about .8.
- Don Klipstein ( snipped-for-privacy@misty.com)
Gee...so much for trying to defend a PF correction feature. :) Now that gizmo just looks like a glorified surge suppressor. I'll take a flying guess at under $5.00 in parts.. :P
D from BC
Yes. Here's a schematic showing a circuit that, unlike the thing shown at the url, _will_ save energy, when properly used:
/ AC ----o o----+ | [Appliance] | AC ------------+
It works for any AC mains powered electrical device.
I second this response. PFC does not magically save power, it only smooths out high peak currents to make the load look more resistive from the power comany's perspective. The power company only cares about power factor when the customer is drawing huge peak currents. Peak currents cause loss in their supply wires which is a loss to their bottom line. That's why power from the power company is supplied in such high voltages, it reduces the current and therefore the resistive loss in the wires.
This box is a scam. Passive or active PFCs with any decent power output have huge components. You would waste more power in the PFC than you would save in the supply wires in a normal house and like I said, the power company does not monitor residential customers for bad power factor.
Traver
You are all right and there is some energy savings, too! The PF is a measure of the phase angle of the VI curves.they also provide "insight" int how much energy is being "wasted" by having a motor ..not operate at its maximum efficiency point/ as IT UNLIKELY TO HAVE A MATCH SYSTEM FOR A SINGLE "POINT", THEN you adjust the V I drive to make a system where the resultant drive waveform when combined with the motor response(s) offers optimal transducer for the given load"
so it means that often motors are over specsed, compared to their nominal load, right. so you need right now 2 units of power asd you spec a motor with 100 units. this lets your mechanical system and some head room for dynamic effects, over coming startup conditions and extra for degradation over time, ,
As it works out the PF is a measure of how lightly loaded the motor is, so you can tell by "looking at the PF" if a V I modfcation can MAKE the system to an optimum point.
the final basis is now for a given nominal load without the "gadget" you get the over spedced motor and performance, by definition ...not optimimzed... then
if you put in basically a "real-time" dynamic load matching device, obtained via waveform modification..then an optimal system, results by definition, and therefore for the same nominal load, the power consumed in an optimized system will be less than an open loop driven system...
sO ITS NO FRAUD AND POSSIBLE. AND EASY TO GET CONFUSED BY DIFFERENT TERMS USED TO DESCRIBE THE PROCESS.
fOR FINANCIAL ANALYSIS AND INTEGRATING YOUR OWN CONTACT A CONSULTANT THAT KNOWS THIS BUSINESS AND CAN QUICKLY GE YOU WHAT YO NEED!
bEST REGARSS, mARC pOPEK
While I share your doubts about the device described at electric-saver.com, it *is* possible to save energy in the case of lightly-loaded electric motors without huge components. For example, see this paper:
The Science Behind the PEC Motor Efficiency Controller
If you look at Figure 9, it becomes apparent that the Nola technique makes the power factor *worse* while saving energy. It would be interesting to do the same with a sine wave that changes amplitude, but it certianly wouldn't be as cheap as the technique described.
Another thing that strikes me about Figure 9 is the fact that it requires something like a Gate Turn Off Thyristor. I suspect that pretty much the same effect could be had with the usual zero- crossing turn off devices.
An escalator is a classic case of a lightly-loaded motor running many hour per day, which is, no doubt, why it was chosen for the test results in Figure 10. That being said, the numbers look about right.
-- Guy Macon
...
Patent for device described above:
Interesting information about Marc Popek:
-- Guy Macon
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