PF correction devices, again

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zog

Senior Member
Location
Charlotte, NC
Hate to bring this up again but the Natioanal Institute of Standards and Technology (NIST)recently did a real study of these scams, er I mean devices so thought I would post link in what I hope is the last discussion we ever see on these PFM boxes.

http://www.nist.gov/eeel/quantum/power_121509.cfm

I hope this opens some eyes to the EC's out there slling these devices under the false belief that they offer any savings to thier victims, er I mean customers.
 

ty

Senior Member
Some plain thievery going on out there. And some electricians just have no idea (so for some, the term electrician must be used loosely).

I actually had one of these given to me a while back. It's still in the box. Yet another one of these guys had called trying to get us to sell his snake oil for him. I posted about the CEO getting on the phone with me.
They believe (or believe to sell) their product, they actually gave me one. And then of course stated something about not being allowed to open it, or it would void the warranty. lol.
 

480sparky

Senior Member
Location
Iowegia
Some plain thievery going on out there. And some electricians just have no idea (so for some, the term electrician must be used loosely).

I actually had one of these given to me a while back. It's still in the box. Yet another one of these guys had called trying to get us to sell his snake oil for him. I posted about the CEO getting on the phone with me.
They believe (or believe to sell) their product, they actually gave me one. And then of course stated something about not being allowed to open it, or it would void the warranty. lol.


If someone sent me one pro bono, I'd crack it open in a heartbeat. Who cares about the warranty?
 

Chamuit

Grumpy Old Man
Location
Texas
Occupation
Electrician
I liked the remark on the greenhouse gases. Damned if you do. Damned if you don't.
 

WinZip

Senior Member
Hate to bring this up again but the Natioanal Institute of Standards and Technology (NIST)recently did a real study of these scams, er I mean devices so thought I would post link in what I hope is the last discussion we ever see on these PFM boxes.

http://www.nist.gov/eeel/quantum/power_121509.cfm

I hope this opens some eyes to the EC's out there slling these devices under the false belief that they offer any savings to thier victims, er I mean customers.

I have a friend I put one of these in for him over a year ago

http://power-save.com/1200.html

His monthly electric bills were averaging 505.00 a month

He has old style ac unit - pool with two motors - older hot tub 50 amp - well pump motor that's just the heavy motor loads.

This unit has been in over one year an his average monthly bills have been 285.00 - 320.00 from 505.00 a month average, so who knows.
 

StephenSDH

Senior Member
Location
Allentown, PA
I have a friend I put one of these in for him over a year ago

http://power-save.com/1200.html

His monthly electric bills were averaging 505.00 a month

He has old style ac unit - pool with two motors - older hot tub 50 amp - well pump motor that's just the heavy motor loads.

This unit has been in over one year an his average monthly bills have been 285.00 - 320.00 from 505.00 a month average, so who knows.

I know. Some people sleep easier at night with a placebo.
 

ty

Senior Member
so who knows.
physics.

I would bet there were some other changes in their day to day lifestyle.
Maybe a kid moved out and went to college, maybe they stoped leaving lights on in rooms, etc... There are way too many variables to concider to even remotely think that magic box has accomplished anything.
 

WinZip

Senior Member
Maybe set up a motor on a test bench run through a KWH meter using a power saver for say 2 weeks 8 hrs a day , then run without a power saver for 2 weeks 8 hrs a day then judge the results.

Worth a try ??
 

gar

Senior Member
Location
Ann Arbor, Michigan
Occupation
EE
100407-0745 EST

WinZip:

There is no possible way for the device you mentioned to produce the the electrical energy savings you describe.

With any reasonable knowledge of electrical theory about circuits you would never propagate such grossly inaccurate information and try to sell what is a fraud.

There is no reason to use a KWH meter to do the test. A far quicker and more useful test is with a wattmeter. You connect the wattmeter, then connect and disconnect the so called power saving device and see how much the power changes. Note: essentially a KWH meter performs an integration of the output of a wattmeter. Integration means summation. In an ordinary rotary type watthour meter the counter (dials from a gear train) is the integrator. The rate of rotation of the disk is the wattmeter.

Do you work for some power saver device company?

.
 

PowerQualityDoctor

Senior Member
Location
Israel
I have a friend I put one of these in for him over a year ago

http://power-save.com/1200.html

His monthly electric bills were averaging 505.00 a month

He has old style ac unit - pool with two motors - older hot tub 50 amp - well pump motor that's just the heavy motor loads.

This unit has been in over one year an his average monthly bills have been 285.00 - 320.00 from 505.00 a month average, so who knows.

They should update their website - they claim for up to 25% saving and your friend gained 37-44% saving...

Something is definitely wrong with the process of measurement - there is no device which can save you so much (except an on/off switch to turn your power down...). Moreover, this is just capacitor, which can reduce your current and kVA rating, but not in kW.


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charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Semi-Retired Electrical Engineer
Maybe set up a motor on a test bench. . . ?
I have seen a video in which one of the purveyors of this type of product used precisely that experiment. It was quite convincing, to the uninformed public at least. If the only load is a motor, and if they just happen to pick a motor with a particularly bad power factor, and if they have a meter showing current to the motor, and if they connect their magic device and the current goes down, it tends to promote the value of their product. But in the normal household power system, motors are but a small portion of the load. If you instead put the meter on the household main, then turned on their test motor with it being just one load and with a few lights, heaters, the tv, and a sterio also running, then switched on their device, then the current to that motor would go down, but the change would not be noticed on the meter that is measuring the entire house load. That video was memorable, to me at least, because it was a well thought out scam.

 

PowerQualityDoctor

Senior Member
Location
Israel
I have seen a video in which one of the purveyors of this type of product used precisely that experiment. It was quite convincing, to the uninformed public at least. If the only load is a motor, and if they just happen to pick a motor with a particularly bad power factor, and if they have a meter showing current to the motor, and if they connect their magic device and the current goes down, it tends to promote the value of their product. But in the normal household power system, motors are but a small portion of the load. If you instead put the meter on the household main, then turned on their test motor with it being just one load and with a few lights, heaters, the tv, and a sterio also running, then switched on their device, then the current to that motor would go down, but the change would not be noticed on the meter that is measuring the entire house load. That video was memorable, to me at least, because it was a well thought out scam.

1. All motors with low load have low power factor. Some air conditions have such conditions during part of their working.
2. Due to the increase of harmonics pollution, the power factor (compared to cosine phi) of many devices are not as high as used to be.
3. Nevertheless, reducing current by improving PF will not reduce your kWh consumption
 

chris1971

Senior Member
Location
Usa
Did a service call for a city water treatment plant. They had just purchased the 'snake oil' and the person at the city claimed that thes devices could help save 20% on electricity. I had a hard time keeping a straight face after hearing that.
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Semi-Retired Electrical Engineer
3. Nevertheless, reducing current by improving PF will not reduce your kWh consumption
Agreed, and I think most of us understand that. It amazes me that the people selling these devices manage to convince their customers otherwise.


By the way, as I recall, the video of which I spoke had the "before and after" readings taken by an ammeter connected to the line side of the test bench. Thus, it was reading the total current, and of course an improvement in power factor would make that reading go down.
 

PowerQualityDoctor

Senior Member
Location
Israel
Agreed, and I think most of us understand that. It amazes me that the people selling these devices manage to convince their customers otherwise.

I am not amazed, I am jealous with this people. The company I work for sell real energy optimizers which provide measurable kWh reduction but we spend so much explaining the results. I wish I could just show some tricks... I have just finished few hours of analysis, got an impressive 15% saving in kWh, sent to the customer, and started to get requests for further explanations... I think the difference is between selling to layman vs. engineers.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
The POCO's are the true beneficiaries, according to the article.

And thus the environment.

I think it should be a law to have them installed on every reactive load and that HO's should be required to have their PF tested once a year by a licensed electrician.
 

zog

Senior Member
Location
Charlotte, NC
The POCO's are the true beneficiaries, according to the article.

And thus the environment.

That is misleading too, the impact these have on the POCO's efficiency is so minor, would take many years to make up the energy used to produce the actual device, not to mention the energy that is consumed by the magic box of capacitors.

I think it should be a law to have them installed on every reactive load and that HO's should be required to have their PF tested once a year by a licensed electrician.
You are joking right?
 

winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
Plausibility question:

I know that a residential KWH meter is supposed to measure _power_ consumption. The theory of the meters that the torque applied to the spinning disk is supposed to be proportional to the instantaneous product of voltage and current. However I have never tested this.

Is it possible that an improved power factor will result in a reduction in the meter reading even if the 'true' power consumption remains the same?

-Jon
 
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