power quality/powerfactor capacitors

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we recently met with a rep concerning power factors capacitors and TVSS claiming that they can cut electrical consumption by up to 15%. Looking for opinions on this subject.
 
Talking residential-----Please do a site search on this subject and the snake oil salesmen that promote this junk, you'll see little positive on the side of this subject. If you are a contractor and you get involved in this IMO you are doing a disservice to your customers, and at some point I think the government will crack down on these charlatans.

Here is one of many

http://forums.mikeholt.com/showthread.php?t=104549&highlight=capacitors
 
The only thing I noticed on a small industrial we work on was a voltage increase after installing a plant PFC. The plant had poor PF and was being penalized. The increased voltage increased the current flow of all the existing motor PFCs resulting in premature failure of them. We had the POCO reduce incoming voltage to about 484 instead of the almost 498 and everything just seems of be hunky dory. We did replace the damaged caps with "hardened" ones. Ask your CH rep they are not in the catalog.

The sales rep said we could see a decrease in power usage but that is not why they were purchased.
 
I would agree with Brian, most of the time when the lead is "cut electrical consumption" it's a snake oil salesman.
If you have a situation where you are being penalized for poor power factor, it's a different story.
Otherwise be leary.
POCO's can often give good advice on this
 
I've read the fine print on two of these so far, and much of their savings claim in the legal-ease is connected to the fact that they are a TVSS also. They will "save" you because less of your stuff will potentially get blown up, not necessarily energy savings. Fact is, in the typical residential setting, they won't save you one nickel.
 
The viability of power factor correction devices for energy-saving is answered on the DOE Energy Star web site.

Do Power Factor Correction Devices (sometimes called Amp Reduction Units or KVAR) really save money? Can they earn the ENERGY STAR label?

I've seen some of these questionable products claim some sort of Energy Star endorsement. You probably can ask if they really are here: Ask A Question

BTW, if that power-factor correction product claims to be Energy Star, send the details to logomisuse@energystar.gov . Maybe if enough people in our industry report these questionable claims, the scamming will stop.
 
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Look up some of these companies, and you can see they won't be around long. Power-Save is worth about a dollar a share now. They were 12-15 bucks at one time. OTCBB: PWSV
 
Many large office buildings have power factor correction capacitor banks mounted at the end of their bus duct risers! I've noticed that about 95 percent of the time their fused disconnects are "OFF" and the other 5 percent have blown fuses ????
 
charlietuna said:
Many large office buildings have power factor correction capacitor banks mounted at the end of their bus duct risers! I've noticed that about 95 percent of the time their fused disconnects are "OFF" and the other 5 percent have blown fuses ????
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Charlie I have seen the same in several data centers and factory's, Expensive equipment with the main disconnect off.
 
electricalperson said:
what would be the reason to shut off a PF correction device? those things should just sit there and no one should touch them unless theres a problem
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Normally they have not been sized correctly, and there is a resonance problem which can cause overvoltage. The overvoltage can cause the capacitor to fail or the sensitive electronic equipment to shut down. I find very few "fixed bank" capacitors that are applied correctly.
 
electricalperson said:
what would be the reason to shut off a PF correction device? those things should just sit there and no one should touch them unless theres a problem
Click to expand...

Why do people turn off the control power to GFP systems?

Not set the LSIG on CBs?

Replace OL's in motor starters with wire?

Because there is wide spread misunderstanding of proper design, installation and operation of electrical systems.
 
TVSS and power consumption

TVSS and power consumption

A few years ago, I helped a contractor who sold TVSSs. I used them successfully in my manufacturing plant. Some of his customers, particularly convenience store operators told us that after installing the TVSS, their electric consumption decreased. After consulting with several others we reached the conclusion that the decrease was due to the capacitive characteristics of the TVSS and the heavy use of AC electric motors in the customers facility. It was not part of the sales presentation or a promise to the customer, although the store operators were extremely pleased. Because the benefits did not occur for all users who needed the TVSSs, we did not market the TVSS as a power factor correction device.
 
brian john said:
Charlie I have seen the same in several data centers and factory's, Expensive equipment with the main disconnect off.
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Brian,

I'm curious about the PF correction hardware you've seen in data centers. A couple of questions:

1. What vintage data centers were they? Large or small?
2. Where in the power system were they deployed, on the UPS output or input?

Thanks,
John
 
electricalperson said:
what would be the reason to shut off a PF correction device? those things should just sit there and no one should touch them unless theres a problem
Click to expand...

The best setup is to have them automatically switch in and out when needed so the voltage does not get too high during light load periods. And a leading power factor is just as bad as a lagging power factor in the utility's eyes and will have the same impact on the bill.
 
The original post stated these devices could save 10 to 15 percent of a customer's billing amount! Consider that ! If this was true, every office building in the USA would be installing them! To a large office building that savings could amount to $70,000 a year --- this equipment isn't that expensive and easy to install ! I have tested a few of these devices for certain customers with data loggers and never found them worth the installation costs....
 
charlietuna said:
The original post stated these devices could save 10 to 15 percent of a customer's billing amount! Consider that ! If this was true, every office building in the USA would be installing them! To a large office building that savings could amount to $70,000 a year --- this equipment isn't that expensive and easy to install ! I have tested a few of these devices for certain customers with data loggers and never found them worth the installation costs....
Click to expand...


I've heard that one of these companies promises a reduction and that actually happens (sort of). Not because of the product but because the installation "has to be done" with a full shutdown. On power-up they point to a measured value, which of course is lower than the baseline value. Only trouble is, it is low because not all loads have not fully "walked in" or because stuff was completely shut off prior to the shut down.

After that, it might be like the The Emperor's New Clothes, the customer doesn't want to admit that they were ripped off.
 
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