Son Agro Ballast Q for Electrical Engineers
 

From the info I have been able to pull from the net the Advance transformer SON AGRO ballast has a power factor of 0.8 which gives the draw of the ballast approx 5.2 amps at 120 volts(whew).

http://www.advancetransformer.com/ec...1627985351.pdf


The Universal/Magnetek SON AGRO ballast doesn't give a power factor but draws considerably less power. Specs state 4.30 amps at 120 volts.

http://ultballastspecs.tsqrd.com/hid/S430MLTAC4M.pdf

Any enginners out there that can comment on the difference between the two ballasts. Seems the Universal ballast would probably be more economical to run.

Bryan, My guess would be that the power factor on the magnateck is 0.9 which would account for the differences..

Hmmm to bad they have no prices on that page.. would be interesting to see how the prices compare.

Steve

I am going to call around next week and see what I can find out.

I am reaching back into my memory a bit but I think it goes something like this. The power factor is not something that you can control, it is controlled by your electric utility. The AC electricity that arrives at your house has a sinusoidal waveform. A very simple analogy would be to think it of as two phasors that roughly are the voltage and the current. If these waveforms arrive at your house in phase then the power factor is 1. If they arrive out of phase then the resultant power that you get is reduced. Altought the mathmatical calculations are not trivial if they are 45 degrees out of phase the resultant power would be about 70 percent of normal If they are 180 degrees the resultant power would be 0. Typical power factors in residential areas are in the region of .8 to .9.. So when you select a ballast the power factor consideration relates to the power you receive. If you have a high power factor (.9) you select a high power factor ballast. If you have a power factor of .8 you select a ballast that operates at that PF. Your lighting supply or local utility can tell you what your power factor is.


So if you have a 1000 W light, and assuming .8 power factor, you have to supply 1250 Watts. Also the ballasts are not 100% efficient so I expect to get 1000 watts of light it takes about 1400 watts.

Basically power ~= voltage*curent*powerfactor

naaa, it is in the ballast.. a .8 PF and a .9 PF ballast will use different amountes of powr on the same circut.. this is why you should het HP factor ballasts when you can to save on your power bills..

Steve

Forgot about the Venture ballast. It has a rated power factor of .9 drawing 4.55 amps

http://www.venturelighting.com/Balla...ame%20Page.htm

In order of efficiency we have

Magnatek/Universal 4.3 amps power factor unknown
Venture 4.55 amps 0.9 power factor
Advance 5.3 amps 0.8 power factor.

I guess the power factor of the Magnatek exceeds 0.9 which i didn't think was possible with HID ballasts. Hmm

Or they are rating it slightly different.. we have seen that befor with pump motors here befor.. :roll:

Steve

steve wrote
Good point. I had forgot about the inductive/capacitive nature of the ballast. This actually makes things worse.

Check this out for an even scarier picture.

http://www.sylvania.com/forum/pdfs/faq0002-0297.pdf

It makes one really want to research a CF before they buy.

You just discarded the most efficient of the ballasts. .9 means it is 90% efficient. .8 is 80% efficient.

And pf is entirely determined by the LOAD after the supply arrives a your home. Not by the Utility company. If that were the case then all the large electricity users such as manufactiring would be getting screwed royally. They pay depending upon how good or bad the powerfactor they are running. Less than 75% they pay almost 20% surcharges(if I remember right). That is why all large end users try to adjust the pf of thier shop to as close to equality as possible. 1.0 or 100%. This is done by finding out whether they are running and inductive or capacitive shop and then adjust accordingly with capacitor banks etc.

Unless you are wanting to run many many units of a NPF ballasts, I wouldn't worry that much about whether you buy a HPF or an NPF. the differences between the two in this case where you are running one maybe two ballasts aren't going to be so extreme as to make a huge difference in our montly bill. That warning that you saw regarding running many NPF ballasts is generally only found in large end users. Not home use. If you were to start drawing so much power that you were up in that category the cops would be visiting you very shortly looking for a grow op. And a BIG one at that.

The amount of money you will save if you are running one ballast of the same wattage where one is a .8 NPF and the other is a .9 HPF ballast will end up being counted in the cents per MONTH ie. Less than one dollar. Basically PF in this hobby will not have a drastic effect on savings going back into your pocket. If you are already running or intend to run a 400W ballast the difference will not noticeable.

Basically, buy the ballast that works how you want it to or works the best. Don't go buy a .5 mind you. But the .1 you are talking about doesn't have that big a change. We aren't high end consumers of electricity. When you measure your daily use in the hundreds of kilowatts or more then start worrying about pf. Here it is a waste of time. You could be enjoying a beer with the energy you are putting into finding out all this info.

:shock:

No kidding! It's like hearing a voice of a ghost! :shock: :wink: :lol:

It's like hearing a voice of a ghost!

:lol:

PS. Thanks for the visit DJ88!

Hello,

Ya Darren is right. And nice to see him still have the highest post count!

Titus

LOL, what? You think he's gonna let Steve topple his post count? :lol:

DOH I knew he had a alternate motive!!!!! :shock: :wink:

Steve

I go for quality now.......

Quantity doesn't mean squat.. ;)

I'd like to see some others say that.. ;)

LOL!

*as he fades into the inky blackness*

How's the tank coming Darren? And, I hope your fingers are healing.

Tell that to EmilyB :wink: :lol: ... J/K

:lol: Cashing in squats is fun too......... :shock: 8) :P

Troy,

Finishing the plumbing right now.

Fingers healing? :?: :?

I'm thinking he means your fingers are able to type again?? :D Good to see the coma wore off!! How ya been?? :P

And we know you have a camera :wink:

Kamera? Huh? Don't own anything of the sort. No modern fandangled stuff like that around here.. I don't like technology... Don't you know it will kill ya.. ;)

Maybe someday soon I'll have pics.. Maybe..

Nice to see you back, Darren. :D

Hi Darren! glad to see you

Hi,

Apparant power (VA) = voltage * current.

True power consumption (W) = power factor * apparant power.

True power consumption is the power that hydro charges us.

With that... Volt = 120V.

Magnatek/Universal 4.3 amps...we will say PF=0.9
True power = 464W

Venture 4.55 amps 0.9 power factor
True power = 491W

Advance 5.3 amps 0.8 power factor.
True power = 508W

Motors sit around the pF of 0.6 to 0.9. Electronic ballasts have a pF of near 1.0

And Darren is correct about the industrial surcharge of 25% for a PF of 0.7 and the PF is cause by the load...not hydro. Hydro provides power factor correction for households on the telephone poles (near the large hanging garbage cans on the telephone pole) and transformer cabinets.

- Victor.

Hello,

Hey last time I went to the IEEE dinner gathering. Some of the old timer (huh huh) EE from BC Hydro said they even have to monitor harmonics coming from large industrial and shopping mall type of customers and the customers have to provide proper correction.

Titus

We could get into calculating the entire power triangle for these ballasts. Why not??? You Forgot VAR's Victor. ;)

Why not make it easy and use cos^-1of the pf gives the phase angle. Then you can figure out all three for each ballast.

And I'd be hesitant to guess that the pf of the Magnatek/universal is .9. We can make the assumption that the VA for the ballast is 516VA(simple math as shown earlier). But beyond that. Not a clue with the data provided. For all we know it is .75. And you know what happens when we make assumptions. You make an A$$ out of U and ME

But once we take a close look on the PDF file for the you can figure it out quite readily. It is given to you. But hidden. ;) kinda.

Lo and behold the wattage consumed is given. And for that aren't familiar with power in the real world there are three components. Watts(which we all know and love to hate), VA(Volt Amps) and VAR(Volt Amp Reactive). These three work together in a interesting way. All of you should remember what a right triangle is from high school right? Getting chills yet? NO? You will. ;)

Ok so we put Watts along the x axis VA turns out to be the Hypotenuse and VAR's are the y axis(positive or negative depending on if the load is inductive or capacative). With that said we can find out the pf of that ballast since we know that the VA is 516 due to the fact that we are making the assumption that out voltage is 120VAC and the rated amperage of the ballast is 4.3amps. Multiply the two together and we get... 516VA. From the data sheet we can find out that the Watts consumed by the ballast is 490. Now's where some simple math comes in. Take your VA and divide it into your wattage. 490W/516VA=0.949612403.
So we have a pf of 0.9496 or say 0.95. A little better than the .9 Victor assumed.. Luckily this time it went to our favor. :D Or we could start doing some work with sines and cosines and figure out the numbers that way. :D

Easy huh?

Titus,

Have you taken a look at tha harmonics that are on a regular power grid. Too cool. :) What a mess. :D

:shock: Hmmm... how can you tell Darren is back in school :roll: :wink:

good to see you have some time free now Darren.. whare are the pics?? :lol:

Steve

Hello,

Nope. Didn't even know they were an issue until the issue was brought up at the dinner.

Titus

Titus,

That's why audiophiles spend thousands of dollars on power supply conditioners, regenerators and power cables :)

- Victor.

Learned that stuff before I was back in school this time. :) Just applying it on MUCH larger scales now. Figuring out what size capacitor banks and such are needed to adjust a lagging or leading power factors to near equality. All to save $$$ you know. ;) Never had to worry too much about it on ship I am betting as we created our own power. Bet you could run more equipment without problems if they were to include selectable/switchable banks of capacitors on the ships. Tho they are running mostly 400 three phase. so who knows and really.. who cares.. lol

The biggest mess I have seen tho is the power network at BCIT. And i am imagining at any large school. With all the computers, lighting and such on the same network, the noise is unbelieveable. It would be impossible to use something such as X10 as it would disappear in all the harmonics and noise in the lines.