Power factor correction circuits

Jr.:

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wye would be 120/208, 120V from any phase to neutral, 208 from any phase to any phase

-Lasse

Since the power companies are regulated, reducing their costs means somewhat less cost for your power.

Dan

Pfc in appliances is cheaper for the power companies. Costs of more VA is cheaper for consumers.

Dan

** Only with large commercial and industrial users - and they have ways of making them comply, like billing them for VA when it exceeds power by a sufficient margin.

For domestic customers, there is NO issue with PF - it is absolutely invisible compared to the HUGE headache created by peak loading.

Household loads have large morn "Power factor correction circuits are essential part of modern household power supplies. "

This was what I replied to - so you and Thompson have it wrong.

.... Phil

.

f making them comply, like billing them for VA when it exceeds power by a s ufficient margin.

visible compared to the HUGE headache created by peak loading.

iods of low consumption - the average load being around 10% of that during peak periods.

largely unused the rest of the time.

I seem to remember reading somewhere that the top 10% of the US generation capacity is only used around 20 hours a year

-Lasse

Of course it doesn't. No brain.

You're not my type either. Go stick your tongue in Slowman's ear.

Yes I know, I have delivered 480 V three phase systems to the US.

In Europe, it is common to have three phase distribution everywhere.

I have a 3 phase stove in my top floor apartment and 3 phase stove and sauna in my summer cottage. Some electric companies do not even offer single phase connections.

If I understand correctly, it is very expensive to get a 3 phase domestic feed (three pigs in the pole) to residential areas in the US, even if the medium voltage lines are three phase.

Here there are power factor correction capacitors scattered around on distribution lines. Some (all?) of them are switched on and off.

Where I am in the US, large industrial users have a second meter that measures "reactive power" (volts and amps 90 degrees out of phase).

The KWh meter also has a "demand" scale that measures the power used over 15 minutes (or similar time). This measures the peak use. (It is reset each time the meter is read.)

There is a significant penalty on the electric bill for reactive power 'used' and peak power. That provides a large incentive to correct the power factor and reduce peak power.

Occasionally there is a question on newsgroups about scam devices that allegedly raise the power factor on residential circuits. They are a scam for several reasons, one of which is that utilities do not have a penalty for power factor on residential circuits.

Above is phase displacement power factor.

Power supplies with rectifiers create "distortion" power factor with a higher peak amps. Europe requires that to be corrected in some cases. Don't know if "modern household power supplies" are included in European regulations. The OP talks about both types of power factor in shallow comments, and is a spammer. Far as I know correction for "modern household power supplies" is not required here. Must be it is not "essential" - the OP is wrong.

These are used for turning inductive loads into resistive loads. Lightly loaded motors generate inductive power, so you need to control the amount of capacitors needed to put the voltage and current into phase.

These PFC requirement in Europe applies for power supplies over 75 W. The requirement for lamps is even lower.

Kind of hard for me to do such a thing, since you'd be in the way, just not enough room for the two of US. Besides, Slowman's has to keep at least one ear open to hear what's coming..

Yawn, what a bore.

Jamie

** But microwave ovens are not one of them.

** The regs set some limits on harmonic currents - they do not require waveform correction by an active PFC circuit. Many items need no change to comply, others need only an inductor or a resistor.

There are many exceptions too - like for entertainment electronics.

... Phil

I've seen enough his stuff here that I routinely tell Google to mark it as spam. If enough of us do it, they'll block him.

It seems to have slowed down the flow of ads offering crib sheets to text books.

--
Bill Sloman, Sydney