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What Happens When the Power Factor Improves?

12/08/2009 12:16 AM

Dear Engineers,

I would like to know the relation between the PF and KVAR, also how the improvmint of the PF will affect the KVAR and the rating of the kW loading?

Moreove, is the improvment of the PF will affect the Electrical Energy billing?

thank you.

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#1

Re: What is the affect of improving the power factor?

12/08/2009 2:25 AM

Here is a layman's EE 0.101 (Rev. 0) explanation (i.e., winging it for the first time).

Apart from my possible butchering of notational conventions, it goes like this:

Incoming power is expressed in VA (volt-amp) = VA (or EI). If the load is nonreactive (i.e., resistive, as in heaters and incandescent lights), it will align in phase with the incoming power.

If the load is inductive (motors, solenoids, etc.), the voltage/current in the load will LAG behind the supply voltage/current by a phase angle conventionally designated as φ (phi). The incoming VA is the hypotenuse of a right triangle. The voltage/current used by the load is the leg of this right triangle corresponding to cos φ. The load uses watts W = VA cos φ. Thus the term cos φ is also called "(lagging) power factor."

The other leg of the right triangle, corresponding to sin φ, is designated by the term VAR (volt-amps reactive). This power goes to various line and heating losses, I forget just what, but it is essentially parasitic.

If the load is capacitive (capacitors), the voltage/current in the load will LEAD ahead of the supply voltage/current. Same as before, but in the opposite direction: "(leading) power factor." This situation is less common, but it can occur.

Because of the opposite directions, one effect may be employed to compensate for the other. The most usual instance is adding capacitance to compensate for inductive motor loads. Motors may typically run at cos φ (power factor) of around 0.8 to 0.9 (less if they are mechanically lightly loaded). Power-factor-correction capacitors are sized to match the VAR of the motor at prevailing conditions. Suitable VAR is about 0.2 VA (a bit more for small motors, a bit less for large).

The foregoing used basic VA, VAR, W units; it would be kVA, kVAR, kW for most industrial applications.

Residential situations have few (or infrequently running) motor loads, except for HVAC. Most utilities do not track power factor for this, so any corrections you apply will not decrease your energy costs. For industrial consumers, power factor often is tracked and billed for, so PF correction capacitors are often a good investment.

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#3
In reply to #1

Re: What is the affect of improving the power factor?

12/09/2009 1:07 AM

Although this post makes for good transfer of some facts the poster should rather have rather just have answered the question instead of becoming too technical and confusing the whole issue.

The short answer in fact is, yes correct or corrected Pf is imprtant, since you will save money if motors run at near 100% efficiency and not ± 80% ( As nearly all motors are only 80 % efficient.)

The reason for this 80% is quite simply becuase any motor needs some current to set up a rotational field. This current is called eddy current. Because this eddy current is almost "powerless" it is called wattless current. Now, the current available from a capacitor is also wattless. Thus you use this wattless current to induce the wattless current in the motor and the "online" current is now available to do the work and bring the effeiency up to near 98%.

No such thing as "losses and parasites". The system is also ONLY applicable to induction motors, or anything that needs induced power. Flourescent light fittings are basically the only other appliance to benefit from Pf.

I trust this will help the original poster a bit better.

As a final, the component between 80% and 98% lagging does convert to money in your pocket. The formula of which vary the world over, as per those local power companies.

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#4
In reply to #3

Re: What is the affect of improving the power factor?

12/09/2009 1:44 AM

Oh- I see- so EVERY SWITCHMODE POWER SUPPLY in tvs etc(PF 50-55%) would save by PF correction?-save who/what-life-supply cost-consumer/power supply Co?.

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#6
In reply to #4

Re: What is the affect of improving the power factor?

12/09/2009 3:51 AM

As i feared, remarks without reading the post properly. I did mention "induction motors"? Tv hardly qualify. My post, and typically, power factor correction, applies to industry, entities that use motors. especially a number of them. Lastly, the power SUPPLY company, corporation or municipality, not tv power supply, bill you on current used. A system called maximum demand is used. The more current, the higher the bill. remember, even wattless current is measured and billed. THUS if you reduce the wattless current component of the bill, you pay less. EACH company have a different formula that is used to calculate the charges. It would be pointless to state our formula here. (just more confusion?)

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#8
In reply to #6

Re: What is the affect of improving the power factor?

12/09/2009 4:22 AM

So you don't know if PF correction to a switch mode supply is worthwhile- anyone who does feel free to reply!.

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#9
In reply to #6

Re: What is the affect of improving the power factor?

12/09/2009 4:25 AM

If a TV power supply (or a multitude of fluorescent lamps) has a PF as low as that, it definitely would qualify as a candidate for PF correction, except for the fact that the load itself is usually small. (And is typically not monitored and billed for on residential systems). Also, the TV power supply comes from the same source as that for whatever motors. Please go back to school and learn the relevant concepts.

That said, your term of "wattless current" is pretty good. (= parasitic, by the way).

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#12
In reply to #9

Re: What is the affect of improving the power factor?

12/09/2009 5:10 AM

Tornado, I could not have said that better (TV supply), however i will never equate an eddy current parasitic. Having said that, i also dont think you just waffle, and have actually enjoyed your posts. Lets not get into a war of words here now.

Kindest

J

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#18
In reply to #12

Re: What is the affect of improving the power factor?

12/09/2009 11:44 AM

jvrj, be careful that you do not annoy the holy lords on this site - they will manage to get your posts deleted and you will never get a GA, yes the most coveted GA, that is what seems to drive most of these retired/nothing else to do old farts.

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#5
In reply to #3

Re: What is the affect of improving the power factor?

12/09/2009 2:20 AM

First, the OP asked for an explanation of PF, which I provided. Maybe some bona fide EEs will weigh in and say whether this explanation was good or not.

Second, I did answer the OP's later question, in two parts: residences offer very limited opportunity for PF correction, but industries are often monitored for this and can profitably correct it.

Third, you confused PF with motor efficiency. PF can be raised from from typically about 0.8 to about 0.98. But that is not really motor efficiency; rather, it is the efficiency of how the electrical system delivers energy to the motor.

Fourth, the term "parasitic" does apply, but is not related to, say, biological parasites.

CR4 does not have a vote scheme for "crummy answer," so my only choice was OT.

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#7
In reply to #5

Re: What is the affect of improving the power factor?

12/09/2009 4:16 AM

Hi Tornado,

No confusion, motor efficiency is DIRECTLY related to PF, and in industry, wether you apply power factor correction to an individual motor or to the entire plant, will have an effect on your utility bill. The advantage of course id that a total installation will give you the benefit of minute savings on units like Air conditioners ( some come with their own caps nowadays)

Maybe the term "parasitic" is used in your part of the world, but i still cant see it. The use of PF is purely to take care of the wattless current ( hardly parasitic if you realise that an eddy current is of utmost importance to generate a magnetic field in an induction motor)

Some of your post is true, and i did acknowlegde that, however you may call my post what you like, some of the forum readers will have by now already formed their own opinion. Those readers that are in the same profession as i am will also quietly nod their head. I simply dont believe in elaborate posts if i am not absolutely sure of the subject.

Kindest regards

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#10
In reply to #3

Re: What is the affect of improving the power factor?

12/09/2009 4:27 AM

Dear Jvri

As far as understand, (Pls correct me if I am missing something) you're in confussion between motor efficiency and the power factor.

Correction on power factor does not correct the efficiency of a motor. Because efficiency of a motor is related with the building technology of the manufacturer.

Of course correcting PF prevents unnecessary losses on the line, to minimize the flowing reactive current. Therefore it is possible to reach the maximum power carrying capacity of the line. Those are the line losses, apart from the motor losses and efficiency.

This means you can not raise the motor efficiency from 80% to 100%.

What we are speaking here is the line's power carrying efficiency.

Kindest regards.

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#11
In reply to #10

Re: What is the affect of improving the power factor?

12/09/2009 5:04 AM

Nezihozfirat, no , again no confusion.

PF have never been about the machanical efficiency of motors, but rather , simplistically put, the efficiency at which the motors, or other electrical equipment, make use of the available current.

It is known that mechanical efficiency will never be 100%, but the idea is to pay less by trying to make 100% USE of the available power.

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#21
In reply to #10

Re: What is the affect of improving the power factor?

12/09/2009 3:14 PM

GA. I agree 100%.

While Jvri has correctly noticed that high efficiency induction motors (usually) have a higher PF, the two are not always related. The design trade off that increase the motor efficiency usually improve its running PF. It also increase the starting current which can be a problem. Finally, it increase the manufacturing cost. Nothing is free.

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#22
In reply to #21

Re: What is the affect of improving the power factor?

12/09/2009 5:06 PM

Yes Markot. You are very right.

Higher efficiency points higher PF. (And also a higher price to purchase such quality motor).

I would like to draw the attention of the friend, of which started this thread for the purpose to easily digest the relationship between the varying parameters.

With the consideration of the efficient of any motor is constant % value

Even though Power Factor is related with the efficiency of the motor, PF strictly varies with the load.

To give an example, PF is nearly 0.15 for an idle running motor (an unloaded motor), since PF rises to 0.97-0.98 at the rated full load.

In other words more slipping at the motor means higher PF.

Therefore it is a good idea to select the motor rating, close to the needed power.

Unnecessary high (Reserve) power means lower PF.

Kindest Regards

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#23
In reply to #22

Re: What is the affect of improving the power factor?

12/09/2009 6:40 PM

Yes, very good info. I will add this.

What we often forget when looking at ratio like PF is that at low load, it doesn't matter if the number is bad as it has little effect on the plant PF.

An idle motor drawing 10A with a PF of 0.2 will have much less effect on the plant PF than when it is running with a PF of 0.8 at 200A. What counts is the KVARS that are generated with respect to the capacity of the feeder.

I don't like ratio-metric measurements like PF as they can give a distorted picture when used alone without info about the rest of the feeder info.

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#13
In reply to #3

Re: What is the affect of improving the power factor?

12/09/2009 8:17 AM

Not eddy current, magnetising current.

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#2

Re: What is the affect of improving the power factor?

12/08/2009 3:05 AM
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#14

Re: What Happens When the Power Factor Improves?

12/09/2009 8:38 AM

These whole post is making me confused and making me forget my electrical engg.

1. Motor efficiency has nothing to do with power factor, simply because the motor will run at the designed power factor for the load (based on slip assuming it is IM). The current will be drawin by it. Py putting a pfc what we are doing it is that the magnetising current (sorry in industry eddies have different meaning and we try to minimise that - laminations et all is done for that ) is getting exchanged between the C and the motors L (equivalent for forming the magnetic field demanded by the load). As far as the same current circulates in the motor coil, the losses in it are same, and it is least bothered whether the apfc is supplying it or the grid is doing it.

2. By putting the apfc, we are reducing the ohmic losses in the line between the supply and the apfc. After apfc, it remains same. Before apfc, only active current is supplied, and the losses are now Iactive2 Rline instead of Itotal2Rline.

3. We at least in our factory pay by the KW (MW for us) and the penalty is put for the average power factor (can be translated to MVA and there by to current if you like)

4. As far as OP is concerned

pf = cosΦ

KW = KVA x pf = KVA cosΦ

KVAr = KVA x sinΦ

The pf improvement is used to directly balance (neutralise) the KVAr and in ideal condition if it is totally balanced, your line KW and KVA equals (cosΦ =1 and hence sinΦ=0)

Unless the pf is low and you are an industrial customer, the improvement in pf will not reduce a single cent from your bill.

Even if you are industrial, and you are better than the demanded pf, the decision has to be judiciosly taken. Since then the pf improvement will reduce the line losses (again in the line between the meter and the apfc). The apfcs are usually not put in highly distributed manner (ie one near every load). And you increase the losses in capacitors (the capacitance too have their dielectric losses). So you save the ohmic losses (line) and increase ohmic losses (capacitor)

In the end even for industry it is the financial trade off.

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#15

Re: What Happens When the Power Factor Improves?

12/09/2009 10:26 AM

In short when a loads power factor goes up, the KVAR needed to power the load goes down and so does the electric bill; that is why Power Factor Correction is a desirable feature.

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#16
In reply to #15

Re: What Happens When the Power Factor Improves?

12/09/2009 11:13 AM

Electricity bill (unless there is a penalty) is unaffected by KVAR.

Please note that the power (KW) is called real power or active power.

KVAr is the imaginary/ reactive power. You do not pay for this. You pay the penalty if it exceeds a limit.

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#17
In reply to #16

Re: What Happens When the Power Factor Improves?

12/09/2009 11:28 AM

You are not entirely correct. You are correct about the KW being the true power used by the load and the difference between the KVAR and KW would not be seen by a battery in a ups system but the utility still has to provide the KVAR and Com Ed does charge a penalty if the a site power factor is too low. Also most power factor correction circuits not only help the power factor but improve the efficiency of the equipment and that does save money.

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#19
In reply to #17

Re: What Happens When the Power Factor Improves?

12/09/2009 1:05 PM

I already mentioned about the penalty factor

Electricity bill (unless there is a penalty).

The pf correction unit should not have any effect on system efficiency. Since the only thing that will save are the line ohmic losses between your meter and the pfc/apfc unit,as I explained above.

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#20
In reply to #19

Re: What Happens When the Power Factor Improves?

12/09/2009 2:21 PM

YOU ARE WRONG AND WHY DO YOU NOT IDENTIFY YOURSELF?

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#24
In reply to #20

Re: What Happens When the Power Factor Improves?

12/09/2009 10:19 PM

can you please explain (without being rude), exactly where is that improvement in efficiency coming from ? How an active/passive power factor controller is going to improve the efficiency of the load?

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#25
In reply to #20

Re: What Happens When the Power Factor Improves?

12/10/2009 3:19 AM

The OP prompted me to post a simple reply, the type of reply I would use with mechanical technicians who have no real interest in electricity, which attracted numerous replies, some valid and mostly factual. A lot was derived from Google. Those ones you disregard since the poster still, and never will know or understand what he posted. One guest in fact did post the Wiki link to PF. Some replies stated silly "facts" like the poster who stated that an idling motor have very bad PF. Obviously way out of his depth. Who in their right mind will install PF correction equipment based on idling motors? You take your FULL inductive load ( in my case only 3.5Mva) and derive the required Mvar for installion to correct to a Pf of 0.98 lagging. Be that as it may. To the guest that suggested i should not upset the "holy" chaps, thank s for the advice but it matters little to me what they post or think. I have been in this plant for 22 years. My electrical designs have been successful, which by the way includes 5 x 220 Kw motor sets. Strangely i have this idea that i know when to say what and back it up with the how. Many apprentices and artisans have passed by me and can look back at a fruitful "education". So in closing i will now consider my contribution to this topic closed. A lot of posters now are simply Googlingand waffling.

Regards from South Africa.

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#26
In reply to #25

Re: What Happens When the Power Factor Improves?

12/10/2009 4:25 AM

Nobody buys and installs a motor only for idle running.

The example of idle running is given to give an idea in the matter of PF variation curve against load variation.

The reason for above example is to make clear that the efficiency of any motor is a constant value, of which indicated on its nameplate. % Efficiency for a certain motor is not a number, varying with the power factor. (Opposite with your explanations)

There is no need to bother yourself in view of taking the bad Power Factor of idling motors into consideration and arrange the capacitor bank accordingly.

Kindest Regards

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#28
In reply to #26

Re: What Happens When the Power Factor Improves?

12/10/2009 9:31 AM

With respect to a motor you are correct but when you have a power factor correction circuit for a Pulse Width Modulated (PWM) device UPS or switch mode power supply the PFC circuit does improve efficiency. The above statement makes no comment about what kind of load it is; it may be a motor but it also could be something else.

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#29
In reply to #28

Re: What Happens When the Power Factor Improves?

12/10/2009 9:56 AM

Yes. All my explanations were covering (Induction) motors (Even the Transformers).

Pulse modulated UPS or other switch mode appliances must be negotiated under a different category.

Most of the UPS suppliers are declaring their products are harmonically boosted and also their Power factor is self corrected inside.

Especially Harmonics are created with higher frequency of mains frequency. Firs, second, third harmonics are the multipliers of the mains frequency.

Therefore behaviour of the capacitors in the PFC unit is different against those harmonics. Because they are calculated in accordance the mains frequency. Higher Frequency means higher capacitive reactive current, and therefore malfunction.

Such Harmonic producing units must be purchased carefully.

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#33
In reply to #28

Re: What Happens When the Power Factor Improves?

12/11/2009 3:40 AM

Again the guest, I don't know why you want to be identified.

If you are putting the pfc post UPS ie trying to correct the load of the UPS, of course the efficiency of the UPS will increase (Since the UPS losses will be depending on the current supplied).

But then how significant it is?

Usually a good UPS will be at 97-98% efficiency.

Assuming it is 97% efficient, thsi will be 96.25% @0.8pf and 94% @0.5pf

The input side pf as the earlier post said are protected not only for pf correction purpose but for the harmonic filtration too. And as the previous post indicated, most of the reputed UPS makers protect the input from pf and harmonic distortions (i have seen, at least in brochures that the pfs at input even at 150% of rating to be >0.99 ( and harmonic distortion less than 4-5%).

Yse the solid state sources lose the efficiency under reactive power, but that is true for any source (Even alternator copper losses go high under reactive load condition)

The question is how much you are taxing the source Vs what you are paying.

And to be very frank, except on load conditions like us (where my factory shed has 3MVA and over all unit has around 25MVA demand), where the load is at least in a bit far into tens of KW or more, the pfc may not be economical.

It is simple you have a load of 80KW on the source at 0.8pf (ie 100KVA).

Put a 100KVA @0.8pf or get a 80KVA @1 pf+ pfc.

The saving in the source is approx 200-300W.

I am not sure about the losses comparison (since the pfc itself will have its losses- control circuit, dielectrics...) - may be about 50 Watts in normal capacitors at this KVAr (good ones @0.5W/KVAr will be 30W)

That may give one a power saving of the order of 150-250W.

And as I said/ and is nothing new , it all boils down to economics.

The problem is OP has given an open ended statement and we are all interpreting/ trying to interpret what he meant and fighting over our convictions .

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#27
In reply to #25

Re: What Happens When the Power Factor Improves?

12/10/2009 5:38 AM

The problem here is that not all are mechanical technicians.

who stated that an idling motor have very bad PF. Obviously way out of his depth.

In my factory the machines are build to their maximum capacity, which is not too oftem met.

Just for an example I have a VTL of 7.5m diameter. The drive motor of the chuck is rated 100KW. That is based on a maximum load rating of >200T (got to check the mechanical spec, but it is some where around it, may be quite a bit more.

The load on this are seldom of that size, diameter, height etc is OK, but the weight will not be even around 20-30T (Hollow, turbine casings). Still once in a while 150T components do come in. And this being the largest lathe in our factory, has to accommodate this.

Now what will be the pf of the main motor on this load?

Infact in my factory shed, we have been doing a load analysis (there are 3 substations 1MVAx 2 + new of 2MVA) for distributing the loads.

We were surprised to see that the old 1MVA substations had connected loads of almost 2MVA each and the over-load trips were rare, they did happen, but may be only a couple of times a year. (The new 2MVA was brought in for expansion and not for thr tripping)

But then since these are machine loads of course usually a lot of them do not run together (eg the U,V,W,X,Y,Z will have motors, only a few will run), and the ones running will run to capacity based on the particular operation.

This is just to show that in typical macine shop with large machines, the average load may be typically 50% of the rated, and that though is not idle still is a poor pf. Of course I can not say the exact value, since in my panel it is post pfc.

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#34
In reply to #25

Re: What Happens When the Power Factor Improves?

12/11/2009 7:04 AM

jvrj, you will notice that your posts have been voted off topic - please do not let this deter you from using this site. The marking of your posts off topic is one of the many methods that the "Holy ones" aided by their friends in Admin actually try to force you away from using this site- it is actually a pity because it is quite a good site. I know this to be true because it has happenned to me.

For the record you are 100% correct in your posts. Best of luck.

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#36
In reply to #34

Re: What Happens When the Power Factor Improves?

12/11/2009 8:35 AM

Hello Guest.

This is the other guest, who had to be identified. .

You are correct in one aspect.

Here there are quite a few people that like to mark GA and OT based on their whims. And that number seem to be a bit too much to be healthy.

Look "You are entirely wrong and why don't you identify yourself" got a GA

However the other statement i don't agree, still, that jvrj is 100% correct. But definitely he is not off topic.

I don't see the people here are mature or maturing.

BTW: I am quite a senior member here with number of posts in comfortably high 4th digit and GAs in 3rd digit, in regular name and may be another 300-400 posts now under guest (not logged in). And that's why I will not identify myself..

And I am sad to see the way GAs and OTs are given. As far as I am concerned, I don't bother about either (and that's why I am unlogged- the GAs are not now going into my account )

What I mentioned, exactly on this aspect is, though that seemed not to have changed the things, is

OT must have been given on posts that are totally unrelated to the subject (none of the OT marked posts unfortunately qualify, of course a few GAs do)

Personal confrontations - should be reported to admin, he can edit off that portion, keeping the subject matter if available intact, or if not he can and does delete the post.

GAs must be given on some thing that is on topic, and some thing new and educative. Look at how many qualify.

And also as I mentioned, when one looks in a long thread, rarely one goes through all the posts. I personally will go through may be first or the second post and then jump to the GAs.

GAs are not for rewarding one, no one gets anything out of it, except may be ego boost. It is for some one who is going to look in a future date for an answer to a similar problem.

The whole purpose is getting lost by

a) The allocations of GAs (mostly personal likes/ hero worship) and OTs (personal dislike)

b) The OP not closing the threads at his satisfaction/ solution of the problem. Especially when the problem is real life one.

This is somehow becoming an exercise in futility. may be that's why you might have seen quite a lot of senior members have become infrequent/ left the forum. Anyway you never joined it .

This is a wholly OT point, and I will mark it as that. In fact I wanted to start a discussion on this subject, but then I have lost the inclination to join the bandwagon again. What I do now is to look once on the forum, in case some one needs help, provide it. And before it is marked OT, hopefully the OP will have a look at it.

Psst: there were a few OTs given to this guest, which later the OP confirmed to be correct. Unfortuneately some insane members removed the OT later and made it unmarked. I would have loved to quote those here.

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#30
In reply to #20

Re: What Happens When the Power Factor Improves?

12/10/2009 10:28 AM

I agree with this Guest. That improving the PF is not the direct cause for equipment efficiency improvements.

In general, IMPROVING THE PLANT POWER FACTOR DOES NOT IMPROVE THE EQUIPMENT EFFICIENCY. It only reduces the distribution losses in the wiring and the transformers because of the reduction of current.

It is false advertisement to claim that adding a capacitor at the terminals of a motor will improve its efficiency. The most one can expect is that the motor terminal voltage will rise because of the better PF seen by the feeder. This usually reduces the motor current and potentially reduces its losses a little (the improvement depends on the type of load). But it is from the increase in line voltage not the improvement in PF at the terminals.

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#31
In reply to #30

Re: What Happens When the Power Factor Improves?

12/11/2009 1:58 AM

Hi again,

This is exactly the reason why posts get distorted and wrong answers come thru. Marcot normally dont post drivel, but here he posted to somebody elses misunderstanding. I'l go to caps.

i NEVER CLAIMED ANY MECHANICAL IMPROVEMENTS DUE TO PF. eNERGY/ELECTRICAL/FINANCIAL EFFICIENCIES-YES.

The best advice i can offer to these late posters is simply- Read and understand the entire thread, then decide if you are capable of posting ANYTHING worthwile.

Regards

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#38
In reply to #19

Re: What Happens When the Power Factor Improves?

12/15/2009 1:40 PM

Cycling reactive currents cause I sq'd R losses (heat), therefore loss of efficiency

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#32

Re: What Happens When the Power Factor Improves?

12/11/2009 2:57 AM

If you improve your PF (by installing PF correction capacitors, for instance) and are an industrial consumer for whom this is monitored, you will decrease your incoming VA (or kVA), which will reduce your electrical bill (assuming that your supplier tracks this).

In most residential situations, your PF is not monitored (partly on account of few or low-time reactive loads), and you will save nothing, or nearly nothing. In the US, there are scammers (or total naifs) who sell $400 boxes containing a $20 capacitor to "correct" residential PF, which is usually not tracked by anyone. (If you also have a fabrication or hobby shop, you might be able to wangle a deal, though.)

Let me be perfectly clear: some posts herein are monumentally confused.

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#35
In reply to #32

Re: What Happens When the Power Factor Improves?

12/11/2009 7:21 AM

thank you Tornado, you are right. And the confusion is actually scary, especially if it comes from engineers

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#37

Re: What Happens When the Power Factor Improves?

12/12/2009 1:02 AM

thank you all, it was useful discussion, in general what i get is , improving of power factor to the industry standard of 0.9 helps in releasing the KVAR loading on the transformers. This means that the kW loading of the transformers can be increased.

regards,

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#39
In reply to #37

Re: What Happens When the Power Factor Improves?

12/15/2009 4:15 PM

Eventually, in result of all discussions in this thread, all hands are agree on the matter of the current carrying capacity of the line can be improved by correcting Power factor. This is obvious yes.

However In my opinion, the reply for the question of the sender is still suspending.

Suggesting he is a home user and supplied with single phase. (Neither an inductive , nor a capacitive counter is installed)

He is asking if the losses across his supply line, due the bad power factor, is being reflected to his bill, since he has only an active Kwh meter.

I say Yes. And will be pleased to hear other ideas

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#40
In reply to #39

Re: What Happens When the Power Factor Improves?

12/16/2009 12:05 AM

ya it is correct, what you said was correct, there is a losses in supply line, so we have to study the improvements of the PF which is affected the bill.

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