Can someone please explain this

[rantoftheday]

Can someone please explain clearly, concisely and briefly what power factor is

I've tried looking at various sites and they go way too far in depth and I get lost.

I just want to know in Laymans terms what it is

And I would also like to know the difference between VA and Watts, again clearly and briefly, explained like i'm an idiot, which some may argue that I am!

The guys in work don't really know how to explain well either

 

[telectrix]

and for the benefit of any female sparks reading this thread, power factor has absolutely no connections with max factor. (runs to find tin hat)

 

[i=p/u]

and you dont wire it up i=p/u

 

[Cyberprog]

I love this forum for the above answers. Everyone sharing there expertise and experience.
My question is can wattless energy be harvested. I was doing a job in a factory recently and the electrical engineer said he was going to use the wattless energy to heat water in the factory. Didn't think it would be possible but was not in a position to disagree. Haven't being back since so don't know outcome.

Remember that in a lot of cases the energy in question is converted into heat and movement, so if he's running some large machines which generate a lot of heat as part of the process, he may be able to capture that heat (energy) using a heat exchanger.
Whether this would be a net gain however depends how much energy has to be inserted to capture the energy in terms of, for example, pumping water through the heat exchanger, and indeed in the initial outlay of piping it all up.

 

[Engineer54]

I love this forum for the above answers. Everyone sharing there expertise and experience.
My question is can wattless energy be harvested. I was doing a job in a factory recently and the electrical engineer said he was going to use the wattless energy to heat water in the factory. Didn't think it would be possible but was not in a position to disagree. Haven't being back since so don't know outcome.

Not in the sense you have taken it!! The only way this Engineer can harvest this wattless current, is by correcting the PF with capacitors at the main switchboard. Which is generally the normal method of not having to pay the leccy companies for all this wattless current, that bigger industrial/commercial installations will suffer from.

Having corrected, then he can provide water heating, (pure resistive load) by using the money saved, to pay for the running costs of the water heater(s)

Now the PF correction by capacitor banks etc ,at the main switchboard will only correct upto the point of capacitor bank connection, everything after the connection point will be still affected by the Original high PF. Companies are not usually too conserned about this, unless they need to free up capacity on sub-main cables. If that's the case, additional capacitor correction will be required at the source, ...ie at large motor terminals, or other large inductive load source's.

 

[Engineer54]

Remember that in a lot of cases the energy in question is converted into heat and movement, so if he's running some large machines which generate a lot of heat as part of the process, he may be able to capture that heat (energy) using a heat exchanger.
Whether this would be a net gain however depends how much energy has to be inserted to capture the energy in terms of, for example, pumping water through the heat exchanger, and indeed in the initial outlay of piping it all up.

You'll still need motors to pump the water thru a heat exchanger. Not very cost effective at all. Unless the whole plant has been set-up for such a system, which would i believe, be an extremely rare occurance in the UK!!

 

[Cyberprog]

You'll still need motors to pump the water thru a heat exchanger. Not very cost effective at all. Unless the whole plant has set-up for such a system, which would i believe, be an extremely rare occurance in the UK!!

Indeed, I did mention that But yes, you'd have to be putting a lot of energy in to get it back out again in terms of pumping. All depends I guess on the heat output of the machines and so on!

 

[Des 56]

Can someone please explain clearly, concisely and briefly what power factor is

I've tried looking at various sites and they go way too far in depth and I get lost.

I just want to know in Laymans terms what it is

And I would also like to know the difference between VA and Watts, again clearly and briefly, explained like i'm an idiot, which some may argue that I am!

The guys in work don't really know how to explain well either

Current and/or voltage of a sine wave

Think of a Cricket guy,he has a bat (voltage) and a ball ( current),the ball is bowled to him

If the bat connects with the ball at the perfect position,the ball will go sailing into heavan
If the bat connects with the ball too early, or even too late,the ball will hardly go past the batsmans crease

Apparant power could be described as the measured result of a perfect hit
True power could be the measurement of where it actually landed

The point of contact of the bat with the ball is varied by the type of gear in the installation
There could be capacitive ( leading) or inductive ( lagging)
The both of them are reactive

True power added to the reactive will equal the apparent power

 

[VoltzElectrical]

Not in the sense you have taken it!! The only way this Engineer can harvest this wattless current, is by correcting the PF with capacitors at the main switchboard. Which is generally the normal method of not having to pay the leccy companies for all this wattless current, that bigger industrial/commercial installations will suffer from.

Having corrected, then he can provide water heating, (pure resistive load) by using the money saved, to pay for the running costs of the water heater(s)

Now the PF correction by capacitor banks etc ,at the main switchboard will only correct upto the point of capacitor bank connection, everything after the connection point will be still affected by the Original high PF. Companies are not usually too conserned about this, unless they need to free up capacity on sub-main cables. If that's the case, additional capacitor correction will be required at the source, ...ie at large motor terminals, or other large inductive load source's.

I think this is possibly the most useful post EVER in terms of my own understanding. Since starting out on this route of discovery, many, many things have seemed too difficult to get my head around, and pf correction is probably right at the top. I never understood how banks of capacitors at the origin of an installation could correct bad pf at source, and now I know! It doesn't! It just stops then getting steep fines from the electrical companies! Hallelujah!

Sometime the penny just drops.

Thanks SO much.

 

[VoltzElectrical]

Eng, now look at my post! I NEED, I NEED!

 

[Engineer54]

I think this is possibly the most useful post EVER in terms of my own understanding. Since starting out on this route of discovery, many, many things have seemed too difficult to get my head around, and pf correction is probably right at the top. I never understood how banks of capacitors at the origin of an installation could correct bad pf at source, and now I know! It doesn't! It just stops then getting steep fines from the electrical companies! Hallelujah!

Sometime the penny just drops.

Thanks SO much.

Glad to be of assistance in getting the penny to drop!! lol!!!

PF correction is an art in it's self, .....Getting it Right i mean and is always a bloody expensive initial outlay. It always comes down to the companies accountants in the end, as in Initial Cost over payback period. The most successful PF correction is by variable auto selective capacitor bank.

 

[GLENNSPARK]

Not in the sense you have taken it!! The only way this Engineer can harvest this wattless current, is by correcting the PF with capacitors at the main switchboard. Which is generally the normal method of not having to pay the leccy companies for all this wattless current, that bigger industrial/commercial installations will suffer from.

Having corrected, then he can provide water heating, (pure resistive load) by using the money saved, to pay for the running costs of the water heater(s)

Now the PF correction by capacitor banks etc ,at the main switchboard will only correct upto the point of capacitor bank connection, everything after the connection point will be still affected by the Original high PF. Companies are not usually too conserned about this, unless they need to free up capacity on sub-main cables. If that's the case, additional capacitor correction will be required at the source, ...ie at large motor terminals, or other large inductive load source's.

Yes and the reason why most inductive loads have inbuilt capacitance so the WHOLE circuit benefits from the correction...........

 

[High Tower]

Tony, Len, E54

Top job guys i have to say!! what makes this forum great!

 

[Engineer54]

Tony, Len, E54

Top job guys i have to say!! what makes this forum great!

Don't forget ''Wirepuller's'' excellent initial description/explanation!!!

 

[FAA Greenie]

Imagine, If you will indulge me, walking into the pub after a hard week at work. All you need is a cold, wonderful pint of lager/bitter/cider, whatever takes your fancy at the time. There is a newbie behind the bar, and you have asked for a pint, the lovely lady pours you a full pint of beverage (APPARENTLY). At a closer look, the (TRUTH) is that in fact that a third of the pint is just froth. So at first glance, you have a full pint of apparent power, but in reallity, you only have two thirds of a pint of true power, the rest is just useless froth that makes up a very non efficient energy source for a thirsty man...