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wat will the power dissipated be???

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You guy study too much and confused:
The simple formular for pwer is:

Power = Vrms * IRms * cosine(Phase angle between I and V)
integral of I or V are wrong. root mean square is the number
 

I have another cooler idea. why do not do something to the meter to read slower? Not vandalizing it the meter but making meter read slower.

I know for sure without doubt this can be done.
 

That's a good idea. I want to save some money for my electric bill.
 

In home or business electric bill savings? If it is home it would be peanuts indeed. Business do pay more for same amount of energy spent than homes in a lot of countries. Where I live small businesses like shops,restorants etc. pay 1.8 higher than homes do pay.
I live in eastern part of US and consume about 300kWatts monthly and cost me 35US dollars. You still can experiment for fun.

Speaking of utilities anyone has a book on legislation/rules overseeing middle man. Some companies provide the energy while buying it themselves from companies which have licenses to opeerate power plants.

Company I use for electric does not produces the electricity. They buy it. They have contract from US goverment to supervise,maintain relay/power line operations which they rent from US goverment and buy electricity from a nuclear power plant and sell it to us.
 

me2please said:
This is interesting! I never know exactly how the meter works.
Do you have any document that can help me learn more about
the meter, flatulent (or others)? 8O :D
You can find some interesting ONLINE facts regarding WH meter as belows:

**broken link removed**

**broken link removed**

**broken link removed**

**broken link removed**

[url]http://www.watthourmeters.com/[/url]



djalli said:
I have another cooler idea. why do not do something to the meter to read slower? Not vandalizing it the meter but making meter read slower.
I know for sure without doubt this can be done.
[Not Sure We Can Discuss This Issue In This Forum Or Not]
YES ... someone has done it. There are many ways to do it. One of them is to put a (strong) permanent magnet near to the meter to slow it down. My colleague from Indonesia (he worked in my country before) told me that in his country, there's a device that can 'stop' the meter running. The device allowed user to select the rotating speed (variable speed selector) of the disk in the meter. In our country, there is a 'LEGAL' device, which is claimed by the distributor to be able to SAVE electricity UP to 30%. However, we doubt it especially for single-phase supply.



tochaHCM said:
You guy study too much and confused:
The simple formular for pwer is:

Power = Vrms * IRms * cosine(Phase angle between I and V)
integral of I or V are wrong. root mean square is the number
Due to the increase of power harmonics in our electricity system, we probably need to use a MORE universal formula as follows:

Power = Sum(Vn x In x cosine(tn))
Vn and In are harmonic components, e.g fundamental, 2nd, 3rd, 4th, 5th, 6th,...etc; tn is the phase shift between each pair of Vn and In.




[url=http://www.public.iastate.edu/~dmumm/Physics222Project.pdf said:
**broken link removed**[/url]]The type of kilowatt-meter that we will model is an induction-type that can only measure single phase AC current. The model is universal with respect to the various manufacturers (Westinghouse, Duncan, Shallenberger, Sangamo). We will assume that the current source and load contribute to a perfect sinusoidal waveform. Waveforms that are not ideal (contains harmonics) can affect the accuracy of any induction-type watt-hour meter."
I wonder whether the Watt-Hour meter (WHM), which wroks based on rotating disk, takes into consideration the harmonic contents of the electricity system or not. Old day AC analog voltage meter (multimeter), which works based on the excitatation of a small motor insides the meter, fails to give accurate result when the electricity voltage waveform is distorted (i.e. non-sinusoidal). Some digital multimeters also do not work well for non-sinusoidal signal (probably those meters assume the signal is sinusoidal). That's why we can see 'TRUE RMS' meter from Fluke or other manufacturers that really takes into account the harmonic contents of the electricity signal. I think 'digital' WHM is available in the market already.
 

Yes, You didn't define How Your System Works.
Problem is Here your System works with 50 Hz but you have Connected that
to 60 Hz System .In Heating Systems in most cases you won't encounter any
problem but in AC Motor Systems the rpm is dependent to it's power frequency.

Now if you had used simple reactive elements such as Capacitor , Inductor ,transformer these elements only change the phase between their
Voltage and their Currents Phase 90 Degree (Lead Or Lag). But they Don't change
the input and output frequency (Eg from 60Hz to 50Hz).

Notice that Ideal Capacitors and Inductors are not Passive Elements
they stores Energy in Half a sine Period and Release the Stores Energy in the Second Half.


So Ideal Cap and Inductors Make Reactive Power .That's Why these Elements
takes more current from Power Line without Using it So if in your area there
are Many Of these Devices Like Motors (In Most Cases they are inductive ) the Power Distributer Company Will Install High Power Big Capacitors to Eliminates
the Phase Shifting Problem to Power Factor Near to 0.8-0.95.

In Industry as they Use Many Motors they Use two Kinds Of Power Meter:
1- Active Power Meter (Kilo Watts Hour)
2- Reactive Power Meter & Phase shift Meter (Kilo Vars Hour)

Although You Don't Use Reactive Power But it's a Penalty for you to Correct
your Power Factor about 0.8-0.9 (By Using Cap)
 

    cedance

    Points: 2
    Helpful Answer Positive Rating
onemilimeter wrote
Is this the only reason why the AC main power frequency was 'choosen' to be 50Hz or 60Hz? But why not 10Hz or 20Hz? Lower frequency, the eddy current losses at transformer also less. Why 50Hz or 60Hz? Is it choosen 'technically' or because of 'conventionally'?


if the frequence goes below 50 hz the lights and equipments will start to flicker since the voltage will vary from 0 to say 220 v fewer times in a second
notice that human eye will notice flickering if it is below 16hz also the transofmer size will icrease with lower freq, so 50 hz is a good compromise.
 

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