Overclocking Lamps And Ballast, The first trip in overdriving MH400,HQI400,MH1000, HQI 250 Options

[arizonavideo]

There is four main ways to make our pj brighter.

1) A more transmissive LCD. New polarizer may help a lot on this as more are found and tried. I would think there will be limit to the contrast v brightness but some improvement would be welcome. I think part of the reason some of the pj look so good is the lower transmissive polarizer they have give vary high contrast.

2) A better reflector system. A small arc condenser system will yield more LUX than a long arc non condenser system. Short arc lamps tend to have a short life but work vary well with reflectors. A parabolic or ellipses reflector could be even brighter than a condenser system if one can be found that will work with longer arc lamps.

3) A larger triplet. The larger the triplet the larger the lamp image can be. This is not a small thing. If the LL standard triplet had a 120mm diameter then the lamp image could be twice as large. You could then use a longer arc lamp or a larger condenser lens [shorter fl] or double the diameter of the reflector system. This would make for a much brighter pj all we need is a 400mm fl x 125mm triplet or doublet? {I have an idea but it has to wait. Would it be twice as bright?]

4) A brighter light source. The 1000 watt system is here but there are some problems. The 80mm arc tube makes an arc image too large for most triplets even the 128mm diameter Buhl lens can't fit all the light in. Any one with the standard or pro lens will only be able to use about 45mm of the arc's 80mm output if they use a 330mm rear fresnel.

SAFTY FIRST

If you always leave your pj on then this might not be the best thing to do. Your lamp life will be shorter and the fire hazard will increase.
I recommend for anyone doing this to make an all steel light box with forced air cooling and safety glass incase of lamp rupture!

A regular lamp will most likely just get dirty inside and the shell will darken to the point that the lamp just doesn’t make enough light to be usable. The new failure mode of an overdriven lamp will be arc tube rupture. I would guess that all the over driven lamp will suffer arc tube failure. All the lamps we use have an extra safety shell but if that shell is over 450deg it too can weaken and break. This could then let the lamp parts arc togather and drop hot melted metal in your box and start a fire.

It gets better if a ballast has a larger capacitor on it will now be able to over heat and smoke too. If your lamp internally shorts out from arc tube failure a normal ballast can operate into a dead short. A ballast that has a larger capacitor will make more current and more heat. A fuse should be added inside the flame proof box for the ballast.

One more thing, the kind of electricity that ballast makes is just the kind that will kill you, High voltage and high current is not what you want to be hit with. If you want to live don't touch the wires when hot.

It is possible to make a standard metal halide lamp brighter by increasing the current to the lamp. The high performance projector lamps have high intensity arc and no extra lamp shell to get in the way of the reflector and condenser. We don't want the high price pj lamps and the short life but we don't really need a 20,000 hour lamp life either so a comprise might be best.

The plan is to overdrive [overclock] the lamps by using a larger ballast or by increasing the power output of the existing ballast by increasing the capacitor value. I don't have an e-ballast and don’t plan on modifying one. If you want to add your ballast to the test feel free to do so.{ Brian said this"The only concern for me is that we won't honor any warranty for a ballast that has been modified or a lamp that has been overdriven.} If you burn out your lamp then don't try to return it.

All the ballats That I will be using will be of the coil and core types. Right now I have a 400 watt M59 CWA ballast and 1500 watt M48 ballast. I will try to find S52 1000 watt HPS ballast.

The capacitors that they use are rated in voltage and microfarads [uf] All 400 watt ballast use a 400 vac cap this is different than 400v or 400 if you see a cap that does not say 400 vac don't use it. In fact unless you know exactly what to look for I would not try any unknown cap. The 1000 watt and 1500 watt ballast use 525vac caps.

I have two GE 400 watt lamps to start testing with. The model # is MVR400/U. This is an ED37 lamp shell which is the big one 4.5" x 11" I got them on eBay for $15.00 delivered so if they don't make it's no great loss. They look to have a 40mm long arc tube by about 33mm wide. This looks just like the 1k lamps but shorter.

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The 40mm arc fits inside a standard triplet and will fit the pro lens also.

The full test of each lamp will include the current of the lamp the voltage the LUX output and the heat of the lamp shell and ballast. I have an old oscilloscope so we can see the waveforms too. I will do some long term testing on mabey one lamp.
My target lifespan for the lamps is 2000 to 4000 hours. Most people will want longer life so should not run there lamps so hard.

More later.

Some test has been done already with the 400 watt GE lamp and look better than I expected.
[Edit]

I have changed lamps to a 400 watt ed ed28 lamp from 1000 bulbs.com

This post has been edited by arizonavideo: Jan 18 2008, 05:20 AM

[benjimatt]

for the 400w setup are you just changing the capacitor to a larger one or are you gonna purchase a whole new ballast

[Mikau]

What about running a 400 watt bulb on a 575, 750, 775 or 875 watt ballast?

http://www.venturelighting.com/BallastHTML...llast.html#750W

And btw, how do you know when its safe to overclock a bulb? (something tells me, you don't) is there only one way to find out? How do you know you won't blow up your projector when you fire it up?

This post has been edited by Mikau: Mar 21 2006, 01:07 AM

[DeathRay64]

We already know that it is risky and can be unsafe. A small amount of overdriving might be OK though. It will definately decrease the life of both the lamp and ballast. Here's a guy that went too far...

http://www.lumenlab.com/forums/index.php?s...&hl=capacitance

[DAZZZLA]

We already know that it is risky and can be unsafe. A small amount of overdriving might be OK though. It will definately decrease the life of both the lamp and ballast. Here's a guy that went too far...

http://www.lumenlab.com/forums/index.php?s...&hl=capacitance

I was waiting for you to post your favourite thread.

DJ

[arizonavideo]

We already know that it is risky and can be unsafe. A small amount of overdriving might be OK though. It will definately decrease the life of both the lamp and ballast. Here's a guy that went too far...

http://www.lumenlab.com/forums/index.php?s...&hl=capacitance

I can't believe you found that thread. I read it a long time ago. He ran a 48uf cap that is double the stock 24uf cap this could deliver almost twice the current to the lamp and he did not add any cooling. He did not say what lamp he had but it might have been one of the S400dd types.

The S400dd type lamps have a smaller arc tube than many 400 watt lamps I think the arc tube is thinner too. I look at them as over clocked to start with only a 10,000 hour life they have half the life of the GE or many other 400 watt lamps. He may have been fine with a 26uf or a 28uf.

There is one more post that I found and the guy has good luck by adding a small amount of capacitance but he didn't say how much he added.

The small t15 and s400DD lamp will not have much room for over driving, with cooling I would think 500 watts or so max. I am not going to try any of the small ones because there is no real reason unless you plan on adding a condenser lens then the smaller arc will pay off more.

This post has been edited by arizonavideo: Mar 23 2006, 09:34 AM

[arizonavideo]

Well I need to get setup for some ballast and lamp testing.

Man I look like a tweaker or something.

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That better.

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Some test equipment I have three multi meters and a laser temp gauge and a scope. I need to start with some baseline readings for the 400 watt ballast and lamp of current, temp and what the wave form looks like.

Hear is a screen shot of the waveform[edit runing the 400 watt lamp at full power] after warm up.

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Never buy a GE ballast this thing is the loudest thing I have ever herd It is way louder than the venture 1500 ballast.


I installed a switch so I could jump in and read the lamp current but the lamp went out. The curent readings are key to determining the true wattage because the resistance of the lamp does change alot as it gets hotter. I need at least to find the missing test leads for one of my meters. It’s a start

I have two ballast a 400watt and a 1500 watt. I will be using both on the 400 watt lamp to see how well the lamp takes it. I have already hooked the 400 watt lamp up to the 1500 watt ballast with the smaller cap[26uf or about 1000 watts] and was ok for the short term.

This post has been edited by arizonavideo: Mar 22 2006, 04:50 AM

[arizonavideo]

The caps that I have right now are a 24uf 400vac, 26uf 525vac, 32uf 525vac, three 2uf 660vac. I could use a 8uf or 10uf just to cover different ranges.

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All can be used on the 400 watt balast but the 1500 watt ballast needs the 525 volt caps.

The ballast the 1500 watt is even bigger than it looks

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.

[kv29]

I think it will be quite difficult to know exactly how long the lamp will work overdriven.
It might do it for 50 hours or 2000. the only way to find out will be using till it meets its maker, isnt it?

Edit: BTW Arizona, I really hope you wont meet yours by doing this.

This post has been edited by kv29: Mar 21 2006, 04:56 PM

[scubasteve2365]

AV, Ive been pondering the thought of this very exact same thing, I just havnt had the time, nor do I have the equipment to do this at home (No Scope, not that its exactly needed).

I have access to a bench at work, that has good analog watt meters on it, and I was gonna ask if I gun use it to run tests, but never really got around to it.

Do you have access to Capacitance/Inductance meter. Id love to know the value of inductance the ballast has. If I were to know this I could probably mathematically calculate the capacitance needed to reach a certain wattage.

Typical M59 ballast will draw 450W, and with a power factor of .95 they deliver ~400W to the bulb. If were to completly correct the power factor (setting it to 1.0) then theorectically you would deliver a full 450W to the lamp.

Its important to know that as you add capacitance you are going to DECREASE the total IMPEDANCE of the circuit. Yes capacitors have Reactive impedance, but we know that the caps impedance(1/2(pi)fc is a lower value than the inductive impedance(2(pi)fl). As Im sure you know Capacitance and Inductance offset each other, so as you raise capacitance you are just gonna begin nullifing the inductance. So as the power to the bulb goes up, you will supply slightly more voltage and more current. (one might think that one component of power would be the primary increase)

Im also very intriqued by the wave form, With a capacitor that big, the time constant must be pretty low (what resistance on the bulb was present, when you took that waveform). It becomes more resembling of a squarewave than a sine wave. If you add capacitance, this wave will probably look even more square. This will also result in more effecient power to the bulb.

[arizonavideo]

I think it will be quite difficult to know exactly how long the lamp will work overdriven.
It might do it for 50 hours or 2000. the only way to find out will be using till it meets its maker, isnt it?

Edit: BTW Arizona, I really hope you wont meet yours by doing this.

We will be able to make a guess of lamp life by knowing about how much a given lamp is over driven and the temps. Some lamp lamp makers may be better than others. Are the eye lamps are supper tuff? Can Venture lamps can take the heat?

Right now we know vary little about how hard the lamps can be driven. Finding the thermal limits is fairly easy, if it melts or explodes then that’s a clue but for long term lamp life there is only one way and that is run the lamp for many hours. I am thinking of making a fixture for long term testing. I can use a light for out side. This still will not let us know the true life because the life of an over driven lamp will be determined by the thermal stress it is exposed to. So running for 12 hours a day may be better than just turning on for a 1 hour movie each day.

I think for any of the 40mm or so arc tubes an extra 100 watts could be had with almost no shorting of life just by adding active cooling. Remer most of these lamps run in steel can with no cooling at all in 100deg heat.

I look at it this way a 27mm arc tube[sd400dd] at 400 watts is 14.8 watts per mm of lamp arc so a 40mm lamp may be able to run at 592 watts with only shorting the life to 10,000 hours. With some cooling mabey 700 watts and a 5000 hour life? Who knows lets find out.

This post has been edited by arizonavideo: Mar 23 2006, 09:41 AM

[mikyd1954]

I like the direction you're taking now, well, except for possible explosions.... anyway, this may be a tad OT but what about the opposite of this thread...can a 250watt ballast drive a 400watt bulb?
not worried about the brightness, just would allow me to test some things and still be able to use my projector .

and back on topis...is it a fairly linear progression as youoverdrive a lamp? ie. 10% more watts, 10% more lumens?

This post has been edited by mikyd1954: Mar 21 2006, 07:51 PM

[Mikau]

Thats a good question Mikyd, I wonder if the lumens per watt ratio is maintained.

[arizonavideo]

AV, Ive been pondering the thought of this very exact same thing, I just havnt had the time, nor do I have the equipment to do this at home (No Scope, not that its exactly needed).

I have access to a bench at work, that has good analog watt meters on it, and I was gonna ask if I gun use it to run tests, but never really got around to it.

Do you have access to Capacitance/Inductance meter. Id love to know the value of inductance the ballast has. If I were to know this I could probably mathematically calculate the capacitance needed to reach a certain wattage.

Typical M59 ballast will draw 450W, and with a power factor of .95 they deliver ~400W to the bulb. If were to completly correct the power factor (setting it to 1.0) then theorectically you would deliver a full 450W to the lamp.

Its important to know that as you add capacitance you are going to DECREASE the total IMPEDANCE of the circuit. Yes capacitors have Reactive impedance, but we know that the caps impedance(1/2(pi)fc is a lower value than the inductive impedance(2(pi)fl). As Im sure you know Capacitance and Inductance offset each other, so as you raise capacitance you are just gonna begin nullifing the inductance. So as the power to the bulb goes up, you will supply slightly more voltage and more current. (one might think that one component of power would be the primary increase)

Im also very intriqued by the wave form, With a capacitor that big, the time constant must be pretty low (what resistance on the bulb was present, when you took that waveform). It becomes more resembling of a squarewave than a sine wave. If you add capacitance, this wave will probably look even more square. This will also result in more effecient power to the bulb.

The term power factor is generally used to express the ability to transfer current into an inductive or capacitive load. The lamp should be almost purely restive so I think they are referring just to the transfer from the primary to secondary. If we change the cap we will make the power factor less and the ballast less efficient. That means more heat. The primary windings will be trying to sink a load into a slightly capacitive load. Because of this I would rather use larger ballast and reduce the cap rather than the other way around. The 1500 watt ballast doesn't even get warm at 1000 watts.

The secondary has three taps and a separate inductor winding. [I found this out with the bad ballast that I had. It had a nick in the inductor] the cap and inductor are mainly to control the current and to provide the high voltage for start up. We can only do so much with just the cap but that is all we can do. I do have a good supply of inductors on hand but I think that would just lower the current.

My Waveteck does cap/ind so I can check the inductance.

Reading the current is more of a problem because I don't have a real amp gauge just the 10 amp max that is in the meters.
I may make a 1 ohm load and measure the voltage drop to determine the current.

[scubasteve2365]

The term power factor is generally used to express the ability to transfer current into an inductive or capacitive load. The lamp should be almost purely restive so I think they are referring just to the transfer from the primary to secondary. If we change the cap we will make the power factor less and the ballast less efficient. That means more heat. The primary windings will be trying to sink a load into a slightly capacitive load. Because of this I would rather use larger ballast and reduce the cap rather than the other way around. The 1500 watt ballast doesn't even get warm at 1000 watts.

The secondary has three taps and a separate inductor winding. [I found this out with the bad ballast that I had. It had a nick in the inductor] the cap and inductor are mainly to control the current and to provide the high voltage for start up. We can only do so much with just the cap but that is all we can do. I do have a good supply of inductors on hand but I think that would just lower the current.

My Waveteck does cap/ind so I can check the inductance.

Reading the current is more of a problem because I don't have a real amp gauge just the 10 amp max that is in the meters.
I may make a 1 ohm load and measure the voltage drop to determine the current.

The power factor in this specific circuit is telling us alot.

A power factor of .90 is telling us that 90% of the power is being dissipated in a Resistive Load (THE BULB) and that 10% is being dissipated in Reactive load (Inductive/capactive impedance losses)

If we raise that power factor to say, .95 then that will up the Power being dissipated on Resistive loads by 5%. In this case, our bulb will see a 5% increase.

As you know, That Capacitive Reactance and Inductive Reactance fight each other. Since the capacitor included with a magnetic ballast is often COINED a POWER FACTOR correction cap. Then you can assume that you begin with a GREATER inductive reactance than a capactive reactance. Thus, if we increase capacitance, more inductance will be offset (circuit will still have a inductive characteristic untill, a Power factor of 1.0 is achieved)

In this case, that is why the effeciency on a M59 Magnetic ballast and the Power Factor are both the same value.

http://www.venturelighting.com/VLPS/Ballas...MH/V90D6412.pdf

you will see that the ballast draws 450W, with 400 of those watts ideally going to the bulb

400/45 = ~.90, in which 0.90 is the power factor of that particular ballast, adding capacitance will increase the power to the bulb. Thats why the guy in the link that deathray gave you blew up the lamp. He increased the Power factor so much,(and probably raised overall total circuit resistance, which sunk more current) that it blew the lamp. He went too far by adding a total of 3 caps, I believe. (which would be ~72uF)

It is possible that if you improve the power factor, that less wattage would be dissipated on the coil, thus perhaps a 400W running cooler.

If the ballast draws 450W with a .9 power factor. Then ~50W is lost on the coil. If we increase that power factor, while MAINTAINING a 450W input. Then you can divert a larger portion of the 450W to the bulb. Perhaps we can put 420W on the bulb, and only 30W on the ballast.

Power factor correction is a big buisness, Companies pay Engineers that are good at power factor correction big big dollars if they can save them alot on their electricity bill. Thats why many plants have large capacitor banks with automated switching. As large motors in the factor change speeds (or a plant only running at 50% production ect), then the power factor can consistently be corrected, meaning the POWER is delivered where you want it to.

Get me the inductance measurements, and I can draw a simulation is Pspice or something, so that we can see the effects over a Broad range of different capacitor values.

Also, if you can give me the resistance values of the lamp. Im sure there is a change when its cold, and when the lamp has reached operating conditions. Im more concerned with its operating conditions measurement.

lastly, I dont expect the frequency to be changed, is it still at approximatly 60Hz with that waveform you showed in the pic above.

[arizonavideo]

For scubasteve

The inductance is .54 henrys for the secondary.


My amp meter is working now and I have a full set or readings. My main concern is not the lamp at this point; it will take a lot more power, but the ballast overheating.

For reference the stock 400 watt lamp and ballast readings with the stock 24uf cap
The stock ballast at startup

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Lamp voltage 135v amps= 2.91 Ballast secondary temp= 214deg LUX at 1m= 343 lamp shell temp =340deg

[edit] Brain fart removed P=VxI so 135v * 2.91= 392 watts the lamp Resistance is E/I so 135/2.19=47ohms

Now with a 26uf cap

Lamp =139v amps= 3.13 Ballast temp secondary = 225deg LUX at 1m=450 lamp shell temp=384

Power is 435 watts the R= 44.4 ohms

And with a 32uf cap

Lamp volts= 146v amps= 4.14 ballast temp=240deg LUX at 1M=690 lamp shell temp=406

Power = 604 watts R= 35.3 ohms

I think This lamp could run at 600 watts for a varry long time . The ballast I'm not so sure.

the 32uf cap wave form

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Some observations.

The lamp is suppose to run at 135v at 3.2 amps with the stock 400 watt ballast and cap. Looking at the wave form it has a nice spike so I bet that the 135 volt reading from my meter is high. None of my meters are true rms so 131 to 133v is more likely true.

The amp readings are low. The stock setup The curent should be at least 3.2 amps instead of 2.91 I don't think the ballast is that far off. The meter that I am using for current is crap but my waveteck I burned out the amp function and the other doesn't read a/c current.

The LUX readings are at 10x again. The room has lots of reflected light so all the readings are good for is to see the % of gain. Going from 343 to 690 is more of a jump than I thing is right. I may do a LUX reading outside for a better reading.

The ballast with the 32uf cap gets too hot to touch and you can smell some burning smell. I did not have any fan or a box just watched it get smoking hot. Even with a fan I think a 32uf cap is a little too much for this ballast. I might make a box and put a 120mm fan on it to see how much it helps. It is new so the smell may be it breaking in. The secondary windings get way hotter than the primaries do so I would put the fan to blow on the secondary first. [The secondary are the big ones]

The lamp was fine, just brighter and hotter I have hit it with a lot more so I think 4.2 amps are fine.

I took more pictures but I lost track of which ones were which

At this point a 28 to 30 cap might be best for the M59 ballast. I have 3-2uf caps so I can edge up to 30uf to see the ballast temps.

I think this is the formla for power. P=V x I Resantance = V/I

This post has been edited by arizonavideo: Mar 23 2006, 09:44 AM

[davidcb]

I need to find the power formula's so we can see the total watts of the lamps[yes I don't rember]

Do you mean these formulas?

P=V^2/R=I^2*R=I*V

David.

[scubasteve2365]

AV

was all those measurements taken at full brightness, I assume it has.



The formula for REAL power is V*I

Other variations for power that include resistance are: V^2/R and I^2 * R

If you wanna count for total circuit power, then you will have to calculate total circuit impedance. This is called Apparant Power.

the resistance of the coil, cap, and lamp combined, over the full secondary voltage and current.

In that case its V*I again, but this could be measured on the primary. Input system voltage and current will tell you how much power is drawn.

Real Power / Apparent Power is the Power Factor. Thats why PF is important when it comes to this.....

What is the resistance on the lamp? and the resistance on the secondary of the transformer.

Moving on to your readings.

The 24uF reading,

135V * 2.91A = 392.85W

The 26uF reading,

139V *3.13A = 435W

The 32uF Reading,

146V * 4.14 = 604.44W

What is happening is that the added capacitance, its changing the power factor like I predicted, but UNFORTUNATLY it is also changing circuit resistance. Meaning that more CURRENT is drawn. As you can see approximatly the same voltage is present in all 3 readings, A 10V window isnt very much, when compared to more than a 33% increase in current. The jump from 2.91A to 4.14A is telling me that the added capactive impedance is playing a huge role.

The effective Impedance of the 3 caps should be:

The 24uF,

1/2(pi)FC = 1/(2)(3.14)(60Hz)(.000024) = 110.62 Ohms

The 26uF,

1/2(pi)FC = 1/(2)(3.14)(60Hz)(.000026) = 102 Ohms

The 32uF,

1/2(pi)FC = 1/(2)(3.14)(60Hz)(.000032) = 82.9 Ohms

The effective impedance of the secondary Coil:

2(pi)(F)(L) = (2)(3.14)(60Hz)(.54) = 203.472 Ohms

So what is happening here is this:

As you increase capacitance, you are increasing the current. This is why the ballast is getting hotter. The resistance is going down. A consistent voltage is applied, so current is rising.

Thats why the manufacturer has the capacitor of 24uF. They could further correct the .9 Power factor, but that does no good if the current goes UP to much. The best solution would be to better the power factor, without DECREASING circuit impedance. That way more of the 450W is diverted to the bulb. What you have above A.V. is more power going to the bulb, but you also have the ballast drawing more power. This means more power is dissipated on the coil as well.

I think the limiting component of this is the BULB. There is nothing we can do to change the resistance of the bulb, hence I predict at best, you could only get away with the 26uF and a shortened lamp life.

This post has been edited by scubasteve2365: Mar 22 2006, 05:48 PM

[paladin]

Zona,

It's probably impossible to tell, but did you happen to notice the lamp color temp changing when testing
larger cap values?

[arizonavideo]

I was wondering what happens to the lamp resistance when it is hit with more current. It lowers. We had 47,44,35 ohms so the more current the lamp sees the lower resistance.

Decreasing resistance is what causes thermal runaway. I think the lowering resistance is only due to the increasing current not the temp.

I can do a simple test this. Take a voltage reading with a fan on the lamp with no reflector then remove the fan and add the reflector centered on the lamp. This will cause the lamp to heat up greatly. If the resistance increases [which it should] then every thing is fine. if it decreases then you have part of the condition for thermal runaway.
The ballast will limit current but if less power is dissipated in the lamp then more power will be dissipated in the ballast causing it to heat up more..

[arizonavideo]

As you increase capacitance, you are increasing the current. This is why the ballast is getting hotter. The resistance is going down. A consistent voltage is applied, so current is rising.

Thats why the manufacturer has the capacitor of 24uF. They could further correct the .9 Power factor, but that does no good if the current goes UP to much. The best solution would be to better the power factor, without DECREASING circuit impedance. That way more of the 450W is diverted to the bulb. What you have above A.V. is more power going to the bulb, but you also have the ballast drawing more power. This means more power is dissipated on the coil as well.

I think the limiting component of this is the BULB. There is nothing we can do to change the resistance of the bulb, hence I predict at best, you could only get away with the 26uF and a shortened lamp life.

To scuba

The power factor can only be correct for a set load.
In normal use the only value that changes is the lamp resistance. Right after start up the voltage across the lamp is 25v so the lamp resistance is 8.6 ohms. The ballast always makes the same current [that why they cal them CCW constant current wattage] the relationship of the inductor and cap is only to control the current in the secondary for a changing load.
Power factor only comes in play if your faze angle is highly inductive or capacitive and Looking at the start up, the wave is almost flat with little cap lag or inductive overshoot, at full power there is more inductive overshootwith though.
By moving away from the standard L/C values wee will lower the total power factor. This is also what I expected. The ballast will waste more power. This is why they have different ballast for different power levels.
I wasn't trying to make the ballast more efficient I was trying to get more power to the lamp.

By looking at the wave form at full power, adding some capacitive would make the impedance closer to zero, but this is a new lamp, a old one may vary well have a lower resistance at the lamps half life and the wave form would be closer to non reactive one.

To paladin

The lamps color temp does look to increase some but I don't have a good way to measure the change.

EDIT the color temp goes down with more power.

I was thinking of shining the light on a screen with two or three other known lights sources. A 3200k 3000k and 2800k lamps and just looking at the difference. Maybe the photo shop experts could come up with some RGB values.

Did any one notice that we made 50% more power with the 32uf cap and the 400 watt ballast? and the lamp seamed fine? This will give you a 50% increases in LUX and lumens.

This post has been edited by arizonavideo: Jul 29 2006, 07:43 AM

[scubasteve2365]

To scuba

The power factor can only be correct for a set load.
In normal use the only value that changes is the lamp resistance. Right after start up the voltage across the lamp is 25v so the lamp resistance is 8.6 ohms. The ballast always makes the same current [that why they cal them CCW constant current wattage] the relationship of the inductor and cap is only to control the current in the secondary for a changing load.
Power factor only comes in play if your faze angle is highly inductive or capacitive and Looking at start up the wave is almost flat with little cap lag or inductive overshoot, at full power there is more capacitive lag with a larger cap and this I expected to see.
By moving away from the standard L/C values wee will lower the total power factor. This is also what I expected. The ballast will waste more power. This is why they have different ballast for different power levels.
I wasn't trying to make the ballast more efficient I was trying to get more power to the lamp.

By looking at the wave form at full power, by adding some inductance would make the impedance closer to zero, but this is a new lamp, a old one may vary well have a lower resistance at the lamps half life and the wave form would be closer to non reactive one.

To paladin

The lamps color temp does look to increase some but I don't have a good way to measure the change.

I was thinking of shining the light on a screen with two or three other known lights sources. A 3200k 3000k and 2800k lamps and just looking at the difference. Maybe the photo shop experts could come up with some RGB values.

Did any one notice that we made 50% more power and the lamp seamed fine? This will give you a 50% increases in LUX and lumens. The 400 watt ballast might not be OK for this but a 1000 watt one with a smaller cap sure would be.

you have an inductor? Most M59 ballasts that I have seen, only have an outboard Cap. Plenty inductance is present in the coil already, no additional inductance should be needed.

I know you werent tryin to make the ballast more effecient, and that your goal was to get more power to the lamp, but it may be better to accomplish that by changing the effiency. However, that may be moot as it may be impossible.

I really do think the Power Factor to be a more important aspect than you are willing to credit it. It comes into play more.

http://www.venturelighting.com/TechCenter/Capacitors.html

When you had the 32uF cap, you had 600W on the lamp. Who knows how much was lost on the coil.

The goal would be to lower resistance, while MAINTAINING Power factor. I know you dont think the power factor means alot, but I think its the key to Overdriving these lamps more controllably, especially since we can regulate power dissipation on the coil.

with 200ohms of inductive impedance, and and 80-110 ohms of capactive impedance the circuit should remain primarliy inductive regardless of which of the 3 capacitors you used. The stock configuration has a 200:110 ohm inductive/capactive ratio. I think the best way to approach this would be LOWER resistance, while mainting that reactive ratio.

Do they make an 27, or 28uF caps in this flavor.

I think 32uf is a bit too much, but I think we can do a little more than 26uf.

If we could lower the capactive impedance to 95 ohms. Then we would need to change the inductive impedance to 175 Ohm, to maintain the same ratio. We could add an inductor in parallel to the coil to do this. that inductor value would be:

200 * ZL / 200 + ZL = 175

200ZL = 35,000 + 175ZL

25ZL = 35,000

ZL = 1400

2(3.14)(60Hz)(L) = 1400

L = 3.72 Henrys.

I think im going to far with this ..... 3.72 Henry inductor probably very hard to find, so mathematically it would work, but realistically probably too hard to track down the components. theory and real world collide again, LMFAO.

What kind of numbers are you getting with the 1000W and small Cap. Im interested in the input power as well.

[mikyd1954]

.....Did any one notice that we made 50% more power and the lamp seamed fine? This will give you a 50% increases in LUX and lumens. The 400 watt ballast might not be OK for this but a 1000 watt one with a smaller cap sure would be.

are you talking about underclocking a 1000 watt ballast to 600?

This post has been edited by mikyd1954: Mar 22 2006, 08:47 PM

[arizonavideo]

I think im going to far with this ..... 3.72 Henry inductor probably very hard to find, so mathematically it would work, but realistically probably too hard to track down the components. theory and real world collide again, LMFAO.

Ya finding a large 3.72 inductor might take some time. Where would you find stuf like that

 P1010029.JPG ( 49.4K ) Number of downloads: 77


oh on my desk.

Seting the power factor back to 90% might reduce the ballast temp some it might be worth a try.

I don't think 3.73 H is right thats more than the total .55 H that is internal to the ballast. How about .373 H?

This post has been edited by arizonavideo: Mar 23 2006, 12:25 AM

[paladin]

That's quite a selection you have there!

You part owner of PartsExpress or something?

Hmmm, chokes for speaker xovers?