Power Factor Correction

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jds

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Gentlemen,
"Power-Save", power correcton device - A boon to mankind or "snake oil"? ?
After extensive research into the liturature claims, including an interview with the author of a Santa Cruz Univ. study done on the device, I have not an ounce of confidence that this will even come close to these claims.
We all know that adding capacitive reactance to an inductive circuit reduces operating costs, and has wide industrial applications.
But suggesting "willy-nilly" that the average house hold or small bisiness can benefit from a "one-size-fits all" approach defies logic?
What say you learned professionals?
Jim Shafer

(Moderator’s Note: Edited to remove email address. If you wish to send an email message to this person, then first send a Private Message via this Forum, and ask for the email address.)
 
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I say first that there are ladies, as well as gentlemen, who participate in this forum. I say secondly that most households and small businesses are not charged an extra fee, by their electric utilities, for having low power factor. I think that is also true for the marina applications that are the focus of your business (based on your profile). Therefore, none would save any money at all, from installing any such devices. And I would say thirdly, with some regret, that most homeowners would not be aware of the facts, and could easily fall victim to an impressive and aggressive sales person.
 
I moved this thread from the "Proposals/Comments for the next NEC cycle" forum after it had been closed since it was not in line with the format layed out for the proposal forum, the reason for closing it was explained by Bob Alexander, AKA moderator rbalex.

In moving the thread I lost Bob's post explaining this
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and I apologize to Bob.

Anyways, Bump!

Roger
 
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jds said:
Gentlemen,
"Power-Save", power correcton device - A boon to mankind or "snake oil"? ?
After extensive research into the liturature claims, including an interview with the author of a Santa Cruz Univ. study done on the device, I have not an ounce of confidence that this will even come close to these claims.
We all know that adding capacitive reactance to an inductive circuit reduces operating costs, and has wide industrial applications.
But suggesting "willy-nilly" that the average house hold or small bisiness can benefit from a "one-size-fits all" approach defies logic?
What say you learned professionals?
Jim Shafer

(Moderator?s Note: Edited to remove email address. If you wish to send an email message to this person, then first send a Private Message via this Forum, and ask for the email address.)
Click to expand...

Properly installed--switched in and out that is, say on a residential AC unit, one might eliminate a bit of heat loss in the wiring, but it is highly improbable that one could ever recoup the initial cost. Furthermore, there is the cost of maintenance--finding and replacing bad caps.

With commercial rates though, there is a PF penalty. One company I worked for in my youth recommended PF correction, but they did not have the engineering talent to specify the details. A bit of engineering is required to do this correctly.
 
Snake oil.

As has been said, PF correction has benefits for large commercial / industrial accounts where they pay a penalty on having poor power factor. But the gross rule-of-thumb on getting PF penalties is that when you order 3 phase service, you will get a PF meter with it and that is used mostly for penalties. I have yet to see a residential or light commercial user with 1 phase service who gets a PF meter. And if you are a 3 phase customer who get penalized for poor PF, there are already dozens of very reputable PFC cap manufacturers who sell industrial grade devices with proper casings, fuse protection, blown fuse indicators etc. none of which their product has, even on the 3 phase versions. The world didn't need another "cheap" purveyor making wild claims to fill a need that was already filled.

As to the common claim that it makes everything run cooler, that's just hair splitting. Technically IF your wires were so undersized that they were heating up and losing energy as a result, you have bigger problems that what that little magic box can solve. If the wires are sized to code, the reduction in heat losses is so minuscule that I doubt it can be effectively measured. They will often also claim that it makes motors run cooler. But that is only true of unloaded motors. Very few motors run unloaded for long enough to worry about and when they do, they run cooler anyway. So the "savings" in heat loss reduction you get from it is only the difference of "normal cooler" vs "PF corrected" cooler, which is again, nothing to write home about. But when they do their comparisons to try to sell these POS devices, they will compare a running motor heat losses to an unloaded motor heat losses with this thing attached. That is a BS comparison (and they know it).

I was brought in to evaluate a claim being made by them to a potential distributor a coupe of years ago. In looking at their website just now, I see they have really toned down their claims and "spin" on the page for the 3 phase / industrial version. But on the residential side they still make the wild "25% savings" claim which is probably worthy of a lawsuit. I know that some of their competitors have been hit by the FTC regarding these claims, these guys are probably on the radar.

http://www.ftc.gov/opa/2002/04/energysurf2002.shtm
 
Matter of fact:

Matter of fact:

If these caps are not switched in and out, but merely tied across the line, they may cause a leading PF which will result in extra dissipation in the wiring. Not good.

Snake oil!
 
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