# "Free" ballasts and adjustable ODNO for smaller bulbs



## Oqsy (Jul 3, 2004)

fantastic idea! i'd been curious about the ballasts inside those bulbs, but never got around to opening one up. of course you'll need to post some pictures and/or diagrams to show the rest of us how you wired the sucker up 

Oqsy


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## DarkCobra (Jun 22, 2004)

Show me the pictures, eh?  That I can do.

Hook up is actually pretty self-explanatory once you've disassembled and seen one of these.

Here's the removed 23W ballast, from a LightWiz lamp. The wires were already attached, I salvaged as much length as I could:










The top two wires go to AC. Each pair of wires on the bottom go to a pair of pins on each end of the fluorescent bulb. The black sleeve on the left AC wire conceals a fuse.

For test connections, I used 4x 1' wires with small insulated spring-loaded hooks on each end, and a line cord with insulated alligator clips on the end. (Yes, I have these kinds of things laying around )

Those with a keen eye will see I've written on the board. Since the casing is gone, I thought it wise to write the wattage on there for later reference. Also, I tested and wrote the operating frequency, 35khz.

I didn't fully disassemble the 14W ballast made by Commercial Electric. The construction was slightly different (and visibly cheaper) than the 23W:










The board-to-bulb connections protrude above the board about 1/4". I bent them outwards for easier access. The ends are marked with a red dot in the photo. This ballast's frequency continuously wandered from 37khz-59khz. I suspect it has a partial component failure - but it doesn't seem to affect the light output.

Let's see some photons. This is 1.5X ODNO, 23W into a 15W GE F15T8-PL/AQ (grow light), with flash on:










And again, with no flash, but with bright room lights and daylight coming in the windows - a rather poor attempt to represent the brightness, but it may give you a general idea:










Experiments I'd like to try, and the anticipated result in parenthesis:

1) Can the ballasts be encapsulated in potting compound/epoxy/paraffin without overheating? (Probably - not much heat)
2) Can they drive two-pin bulbs? (Most likely, just a matter of figuring out which wire out of each pair to use, or if the wires need to be joined)
3) Can they be modified/heatsinked for greater power? (Since they don't get very hot, I think this is possible, not sure it's worth the effort though)
4) Can the output of two be combined for greater power? (Not directly, each will operate at a different frequency and the AC will cancel out. Might be possible to rectify the output of each to DC, then combine - not sure what effect this will have on bulb efficiency or lifetime)

-DarkCobra


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## Oqsy (Jul 3, 2004)

this is exactly the kind of post that keeps me coming back to this board. FANTASTIC illustrations and explanation! I have a couple of 26 watt screw-ins in my current hood, but I'm not ecstatic about the poor spread of light through the front portion of the tank. running each of those ballasts to a separate bulb would do wonders for the appearance of my tank. I just hope the brand that I have are as straightforward as yours. I also wonder about using these to OD small (13w) power compacts in something like a 10g or smaller. you could really light up a nano tank with a couple of 23-26w ballasts and a couple of 13w pc bulbs. 
Thanks for a great idea!
Oqsy


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## creepingdeath086 (Aug 21, 2004)

*hot damn*

i didnt even realize they had a balast, when the light i have dies, its getting the hacksaw too, thanks for posting this, that is really cool, what do you do for a living?


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## DarkCobra (Jun 22, 2004)

Thanks for the kind words. I'm just folllowing the lead of the other greats here. It really wasn't until I found this forum that I believed "yes, I *will* succeed in having a planted tank!"

I have similar goals in mind as you. My 10 gallon planted tank uses two 23W screw-in fluorescents in a standard incandescent hood. This hood is an ancient one in a style apparently no longer made - it's unusually roomy, and made to be placed in the front of the tank, but can be slid back to the middle. This works out very well in terms of light distribution.

Now I want to convert my 2nd 10 gallon to planted, and since its modern hood isn't so versatile, I want to build one. Two or three F15T8 18" bulbs would provide uniform light distribution, better efficiency (much less restrike than spirals), and if driven by three-way ballasts, let me crank up or turn down the light as desired.

-DarkCobra


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## Oqsy (Jul 3, 2004)

independent confirmation...

i was so interested in giving this a shot that I went ahead and opened some pretty old 19w jobs from HD (commercial electric). I have 2 15w fixtures over my malawi mbuna tank, and since there are no plants and the fish are from deeper waters, I've never really sought after a lot of light on that tank. However, the fixtures are both cheapo magnetic ballast "comes with the tank kit" strip lights. I've noticed that they hum extremely loud (i can hear it over the splashing of the bio wheels in the emperor 400 less than 6 inches away). So I decided this was the perfect application for a very slightly overdriven set of 15w bulbs on electronic ballasts. the bulbs I had were identical in circuitry to the 14w commercial electric in the diagram. it took a little work to get the bulb leads connected, and I would have preferred the insulated wires of the other bulb shown, but I digress. The bulbs were relatively easy to open (took a pipe wrench and gradually increased the pressure until it started to pop a bit. that was enough to loosen the glue and they opened right up with no damage to the electronics. clipped the wires from the bulb and the ac line and wired it up in less that 5 minutes. plugged it in, and with only a 5w increase in power, I could still tell it was brighter. it's no 4x OD, but it works perfectly for my setup. The more important thing, NO hum at all. crisp light, no hum, and INSTANT START! no more flickering for 10 seconds before they start. highly recommended mod if you have the right application and the right tools. 

Oqsy


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## DarkCobra (Jun 22, 2004)

creepingdeath086 said:


> i didnt even realize they had a balast, when the light i have dies, its getting the hacksaw too, thanks for posting this, that is really cool, what do you do for a living?


Yeah, it's amazing what's considered disposable nowadays.

I do computer programming, networking, construction and repair for a living. Electronics is one of my hobbies.

-DarkCobra


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## DarkCobra (Jun 22, 2004)

Oqsy said:


> independent confirmation...


Awesome! roud: 

Make sure there's no chance water or condensation can contact the ballast. One of my first spiral lights in aquarium use died violently after a few months - apparently as a result of condensation collecting in the hood, dripping onto the bulb casing, and seeping in through the seams. I came home to a room full of chemical smoke and a faint crackling noise - not to mention some VERY terrified cats. Ballast autopsy showed fire/arc damage, and corrosion indicating water had been in there a while. I'm lucky the damage ended with the bulb.

Since then I seal every seam, ventilation hole, and anything else water might leak into on a bulb with silicone prior to aquarium use. No further problems in several years.

-DarkCobra


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## Oqsy (Jul 3, 2004)

yep, they're very well protected, in fact moreso than the magnetics that preceded them. my wife was pleasantly surprised at the lack of hum and ease of switching them on and off this evening when i showed her the new trick.


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## Opiesilver (Nov 3, 2003)

DarkCobra said:


> I do computer programming, networking, construction and repair for a living. Electronics is one of my hobbies.
> 
> -DarkCobra


You're a BOFH!! Always tinkering huh? I've just got to try this one now.


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## DarkCobra (Jun 22, 2004)

Opiesilver said:


> You're a BOFH!! Always tinkering huh? I've just got to try this one now.


Yes, I am. Pardon me while I glue 60-grit sandpaper in some unsuspecting luser's DVD burner... :tongue: 

Oh, and let me know how it goes if you try it.

-DarkCobra


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## Opiesilver (Nov 3, 2003)

I was thinking maybe you could just wire that up to the door knob of the computer room myself. LOL!!


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## compulsion (Mar 2, 2004)

damnit and i just thrown one away, this would be good for my mums smaller tank with her 15W.. i have a 23W compact left over when it dies.. ill also do this, ive been wondering whats in them and i thought it would be to small to be magnetic. thanks for the useful and ingenious idea. this will be great for people running nanos and smaller tanks.. i rekon there pretty similar to a cold cathode ballast by the looks of things. indeed very much the same size 
roud:


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## Oqsy (Jul 3, 2004)

darkcobra just pm'd me a follow up question on how my cfl ballasts were holding up... here's my response, many months after installing them for anyone that's interested in the longer term viability of this trick.



Oqsy said:


> I just took that fixture down 2 weeks ago, and not because of any problems, but because I was switching that tank to a new fixture that's housing a 2x55w AHS kit. Those lights with the ballasts still work like a charm, and took care of the awful humming that was coming from that tank


yep, those lights are actually for sale with my 29g setup that's posted in the swap/shop section. I'm considering trying this on some tiny NO t5's from the hardware store for a nano hood for my desktop shrimp vase (search the nanos forum for that experiment if it ever happens) Thanks again DarkCobra for the great idea.

Oqsy


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## DarkCobra (Jun 22, 2004)

Thanks for posting the update, Oqsy.

Has anyone else tried this, or is still considering trying it?


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## intermision (Nov 7, 2005)

I'm gonna try this with one of my 23w lights.

Edit I just insalled the new ballast I can realy tell a differance in the brightness. I think I am going to use a small gladware container to waterproof the ballast.

Edit Edit after testing with the multimeter I discovered that the ballast actually puts out 26w.


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## andrewwl (May 3, 2004)

How did you measure the operating frequency? If oscilloscope, which wires were tapped?

You're other inputs are straight into wall AC?

An finally, can you tell me what pins are receiving what from the ballast? (out 
of the four pins of the bulb?)

Fantastic idea btw


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## DarkCobra (Jun 22, 2004)

andrewwl said:


> How did you measure the operating frequency? If oscilloscope, which wires were tapped?


I used a frequency counter. Bring the probe close to the glass of the bulb - the signal is coupled capacitively and no electrical contact is required.



andrewwl said:


> You're other inputs are straight into wall AC?


Yep.



andrewwl said:


> An finally, can you tell me what pins are receiving what from the ballast? (out of the four pins of the bulb?)


Nope, I didn't 'scope them, or check the voltage or amperage. But I can explain the theory of how these compact ballasts work, based on reference designs from several IC manufacturers:










Pins 1 and 3 are fed high-frequency, high-voltage AC from the ballast.

Pin 2 is connected through the bulb's filament to pin 1. Likewise for pins 4 and 3. The filament is essentially a low-value resistor.

Inside the ballast, a capacitor is connected between pins 2 and 4. This provides an alternate route of conduction for the AC - through the filaments and capacitor. But the size of the capacitor is small enough that it isn't able to conduct much power at the ballast's normal operating frequency.

The ballast ignites the bulb by starting at a higher frequency, at which the capacitor can carry more power, thus increasing the current flow through the filaments on both ends and heating them up slightly. After steady ignition is detected, the ballast gradually reduces the frequency down to normal, typically over a few seconds.

Simple yet effective. And also somewhat redundant. The bulb will normally light regardless of whether the ballast initially heats the filaments. Even though a cold bulb doesn't allow direct (resistive) current flow from one end to the other, it can still carry enough current to ionize the gas and get things going because it acts as a capacitor itself at the high starting frequency!

That's why these bulbs come on instantly. Or at least they do until they get old, then they may take a second or two, and sputter a bit until they warm up. That's where the ballast's filament heating capability comes to the rescue, extending the useable life of the bulb.

Wiring to the bulb is non-critical, as long as you keep the pairs together on opposite sides of the bulb. For example, you could swap pins 1 & 2, or pins 3 & 4, or turn the bulb around... doesn't matter in the least.

In all reference designs I've seen, there's no reason why you can't connect pins 1+2, 3+4 together to light a 2-pin cold cathode tube. Your ballast, of course, could be a weird one so I make no guarantees!

You absolutely CANNOT connect two of these ballasts together to provide more power to a single tube. They'd be operating out of sync, at different frequencies, and feeding power into each other instead of the tube - even if both ballasts were exactly the same. Compare this to ballasts made specifically to drive more than one tube - you CAN connect the leads for higher power because it only has one oscillator.

Any other questions?


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## intermision (Nov 7, 2005)

Could you run the ballasts in paralel if you were so inclined?


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## DarkCobra (Jun 22, 2004)

intermision said:


> Could you run the ballasts in paralel if you were so inclined?


If by parallel you mean interconnecting the output leads of one ballast with the output leads of another ballast in any way, shape or form, the answer is NO. The ballasts will burn or at least not operate properly.

The reason for that is explained in my previous post (read the 2nd to last paragraph), but it's buried under so much other "ballast theory" that I expect most people's eyes have glazed over by that point. :icon_redf 

In retrospect, I may have made a mistake in associating my idea with the term ODNO. ODNO is short for Over Driven Normal Output - taking a normal output bulb and overdriving it. While my idea matches that description, to my knowledge all other ODNO experiments have involved paralleling ballast outputs. So when I call this ODNO, one might fairly assume paralleling is involved, when it is not.


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## intermision (Nov 7, 2005)

Are there different kinds of electric balasts?


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## DarkCobra (Jun 22, 2004)

intermision said:


> Are there different kinds of electric balasts?


Yep. Be a little more specific with the question and I can give you a more specific answer


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## andrewwl (May 3, 2004)

*still don't fully understand, sorry*



DarkCobra said:


> Any other questions?


Yes.



DarkCobra said:


> Pins 1 and 3 are fed high-frequency, high-voltage AC from the ballast.
> 
> Pin 2 is connected through the bulb's filament to pin 1. Likewise for pins 4 and 3. The filament is essentially a low-value resistor.


Correct me if I go wrong - "AC Current" I think of some potential A and some reference potential G, and the difference between the two grows and shrinks (one period) over and over, the frequency of course being the inverse of this period. That difference in potential then makes the current flow back and forth, hence the "alternating" in alternating current.

So when you say pins 1 and 3 are fed the hi-freq, hi-volt AC, between what two pins is the voltage alternating? Maybe you could do another drawing showing the path of current flow. The gas in the bulb ends up being a conductor too, doesn't it?


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## intermision (Nov 7, 2005)

DarkCobra said:


> Yep. Be a little more specific with the question and I can give you a more specific answer


Why can some balasts be paaleled and others can't ?


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## DarkCobra (Jun 22, 2004)

andrewwl said:


> Correct me if I go wrong...hence the "alternating" in alternating current.


Yep.



andrewwl said:


> So when you say pins 1 and 3 are fed the hi-freq, hi-volt AC, between what two pins is the voltage alternating? Maybe you could do another drawing showing the path of current flow.


I was afraid you were going to say that. My drawing skills suck, I'm much more comfortable working with photographs. But here's a quick diagram, slapped together in MS Paint, illustrating what I previously described:










Filaments are drawn in red, wires in blue.



andrewwl said:


> The gas in the bulb ends up being a conductor too, doesn't it?


Yep. And since you have now forced me to publicly embarass myself, I will take this question as an opportunity to demonstrate further, in a medium I am more comfortable in, and in a way that helps me restore my ego. 










This is me. Holding one wire of a 15,000 volt power supply in one hand, and a camera in the other. Yes, it is on. Yes, you can feel the power even through the heavy insulation. Yes, the camera was having a hard time autofocusing because the user was highly charged. Need I even say it - DON'T TRY THIS AT HOME!! (At least not your home, you're welcome to do it at mine.)

Imagine that this power supply is the AC portion of the ballast as in the diagram above. The tips of the wires are the filaments. The air between the wires is the gas in the fluorescent tube. And it is not conductive. Yet.

The first thing the ballast tries to do is brute-force an initial arc between the filaments and through the gas in the tube. Remember I said that it starts off at a higher frequency? That helps it jump the gap without resorting to ridiculously high voltages. I can't change the frequency of this power supply, so I *am* resorting to ridiculously high voltages, and also bringing the wires just a tiny bit closer together...










HOUSTON! WE HAVE IGNITION! The gas is now both heated and heavily ionized. Which means it's now fairly conductive, and it's much easier to maintain the arc. Let's pull the wires apart and see what happens:










For some reason, I had a strong desire to look for a jumbo marshmallow at this point.

If we did this in a glass tube to contain the arc, we could pull the wires even further apart. But in open air, the heat of the arc is about ready to make it fly up off the wires, breaking the circuit.

This demonstrates cold-starting of a fluorescent tube. The advantage of doing it this way is that it turns on instantly - the filaments do not require time to warm up. Cold-cathode tubes, which have only a single pin on each side, ignite on this principle alone.

What if the ballast fails to start the bulb this way? Time for "Plan B" - preheat starting. The ballast starts heating the filaments to the point where they start to glow, like an incandescent light on a low dimmer. This invokes the "thermionic effect" - electrons literally start boiling right off the wire and are ejected into the surrounding gas, making it even easier to start the arc. Had I heated the wire tips in the above experiment, I could have struck the arc at a greater distance. NO, I will not hold my butane lighter up to the wires to demonstrate. :tongue:

Heating the filaments is the job of the capacitor. All you really need to know about the capacitor is that at higher frequency AC, the capacitor can carry more AC current. And since the ballast runs at a higher frequency until things get started, and the AC can't flow through the tube yet, the only place it can go is through the capacitor, via the filaments. The filaments start heating up, and at some point the arc will strike.

If the arc still doesn't strike, it's time for a new bulb.

Any more questions?


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## DarkCobra (Jun 22, 2004)

intermision said:


> Why can some balasts be paaleled and others can't ?


Short answer: You can never parallel the outputs from two *separate* ballasts, but you can parallel the outputs from a *single* ballast that's designed to drive more than one bulb.

Long answer: Ballasts work on AC, which means they alternate the direction current flows through the bulb - first it pushes the current through one way, then it reverses and pulls it through the other way. The reversal happens tens of thousands of times per second, at whatever rate the ballast feels like. For a *single* ballast with multiple outputs, all outputs push and pull together, in perfect time with each other, so they cooperate and there are no problems connecting them together. But if you connect two *separate* ballasts together, they are NOT in sync. One will often be pulling while the other one is pushing - they'll be trying to light each other up instead of the bulb! Very, very bad.


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## andrewwl (May 3, 2004)

Bravo! DarkCobra puts himself at risk to enlighten PT members! Very interesting photographs, thank you.


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## A Hill (Jul 25, 2005)

very very interesting.... sounds like what one of my friends did for a science fair last year... his thing was the testoll coil or whatever the guys name was and the thery was that electricity could be transmitted thru the air and power and object for his presentation he made a small coil and powered a flourencent light fixture like you have pictured above.... now while typing this i thought of an ingenous idea! how would u like lights with no cords? wouldnt that be nice? now we are going to have to do some research on that one i bet roud: 

but it is possible one thing i am also thinking of... if you have electricity running thru the air.... what about that big jar of water sitting next to it? what to let it conduct it im guessing water? ill have to find out some more about this......... :icon_roll :icon_roll :icon_roll 

(and if u make a coil dont grab it...... :icon_roll )

Fn


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## Lorenceo (Jan 29, 2004)

Great thread man!
Next time one of these bulbs dies, I will be trying this. roud:
btw, that arcing is so cool!


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## Accident (Dec 12, 2005)

I just threw out a bunch of 23 watt bulbs, dang! Well, I took your idea and applied it to a 10 gallon light that is noisey. It hums really loud even after I replaced that little starter part that looks like a tiny beer can. Tore open a 14watt screw in bulb with a carbide bit in a dremmel and wired it up for the 14 watt long bulb. It works great! Silent as a mouse fart! I cant wait for one of my 23 watt'ers to go out so I can over drive it. Thanx for the tips.
Accident:thumbsup:


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## Accident (Dec 12, 2005)

I'll bet you Gomers are gonna want pix too!!? Ok, I'll see if I can manage it.
Accident
:icon_eek:
Now that I know it works, I'm gonna take out the old transformer to lighten the load.


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## Accident (Dec 12, 2005)

You can see the old starter that was causing all the noise. The silver box/heatsink holds the original transformer that I'm gonna remove. I wish I had thought of it. Oh, well, on to growing more plants!
Accident


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## DarkCobra (Jun 22, 2004)

Sweet!! First pics of an actual retrofit. Thanks, Accident! :thumbsup: 

I assume these are your test pics, and you'll be insulating the final installation.

On a general note - the price of spiral lights has continued to go down since I first reported this technique. I saw a 3-pack of GE 20W spirals in the store for just $8.


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## Accident (Dec 12, 2005)

Yes, just the test. I didnt have time to button it all up as my camera gave me some trouble. I have a 150 watt screw in ballast that has one of those big circular Fluoros on it. I wonder if that would over drive the 2x40 fixture I have? It has a nice plug coming outta it. Im gonna see if it will fit on a square pin compact fluoro. Same kind of bulb?
Anyway cool info, thanx again.
Accident:thumbsup:


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## hyunbaw (Jan 18, 2006)

*2-pins*

Hey,

Great idea. My eclipse 12's light broke and so I tried replacing the ballast, and it worked! Since the old ballast was encased in epoxy, I just had to saw that part off and throw it away. I cut and kept the power cord though. 

As for hooking up 2-pins, you connect the INNER two leads TOGETHER and simply use the outer two leads. I opened up my used-up 2pin bulb to make sure, and basically I saw 4 leads. The inner two leads were connected together with a safety fuse in between, and the outer two leads were connected to the pins. 

Instead of waterproofing completely, I decided to make a "remote ballast" by connecting extension wires, placing the ballast outside of the tank. I still enclosed it as best I could so that no accidental drip would touch it. 

Hope this helps.
Thanks again for the idea!

Billy


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## Wasserpest (Jun 12, 2003)

Just wanted to thank DC for posting this...

I used this method to light two 24W HO T5's, and used ballasts from cheapo $1 23W screw-ins. Works great!




























I documented this in my 36 corner tank thread, but all the credit for the idea goes to DarkCobra. Amazing stuff. And I think you're nuts for doing high voltage arc's with wires that you hold in your hand! :eek5:


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## DarkCobra (Jun 22, 2004)

Wow, two more reports in one day!

*Hyunbaw*: Congrats on getting a two-pin light running! I'm not sure if connecting the two inner leads together would be correct for all recycled ballasts though - others may work differently.

*Wasserpest*: You've retained the original ballast casing - good idea! I think I see a pry mark on it - were you able to just pry it open with a screwdriver?


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## Wasserpest (Jun 12, 2003)

DarkCobra said:


> *Wasserpest*: You've retained the original ballast casing - good idea! I think I see a pry mark on it - were you able to just pry it open with a screwdriver?


Sharp eyes! That's right, the housing just popped open with a flat screwdriver (or knife). I ended up hacksawing off the screw-in part to make the whole thing smaller to fit into the fixture behind the reflectors. As you can see in the last pic.


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## metfan581 (Aug 19, 2005)

Wasserpest said:


> Just wanted to thank DC for posting this...
> 
> I used this method to light two 24W HO T5's, and used ballasts from cheapo $1 23W screw-ins. Works great!
> 
> ...


are you going to add a reflector
do you have a pic


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## DarkCobra (Jun 22, 2004)

He's got pictures of his entire tank build here. Check it out, it's pretty cool.


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## Hoppy (Dec 24, 2005)

My local hardware store has some spiral pc's on sale for 98 cents or $1.49, depending on wattage. It would even be economical to buy one and sacrifice it on the altar of the fish tank! This may be my next DIY job in a couple of months. I think I would get a cheapo electronic box and mount it on the back of the hood with this jury rigged ballast in it - no water damage then.


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## Wasserpest (Jun 12, 2003)

Thanks for the reference DC...



metfan581 said:


> are you going to add a reflector
> do you have a pic


You can see the clipped on Icecap reflector in the first of the three pictures that I posted here. (It still has the protective cover with the UPC on it...)


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## metfan581 (Aug 19, 2005)

one more qu
how often do these ballasts last
How dose it compare to the "stock screw in ballast"
which do you suggest


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## metfan581 (Aug 19, 2005)

everyone is using these:
http://www.homedepot.com/prel80/HDU...earchResults.jsp&MID=9876&N=2984+4233&pos=n12

can/how could u use these:
http://www.homedepot.com/prel80/HDU...earchResults.jsp&MID=9876&N=2984+4233&pos=n12


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## DarkCobra (Jun 22, 2004)

metfan581 said:


> how often do these ballasts last


Hard to say. I've been using spirals in my house longer than my aquarium. All the ones that have failed and that I bothered to check showed blackening at the tube ends - suggesting tube failure, not ballast failure.

With the exception of one I got brackish water in, and the ballast failed... but that's my own fault. 

Since they run so cool, I would expect them to last a long time.



metfan581 said:


> How dose it compare to the "stock screw in ballast"


I'm not sure what that is.



metfan581 said:


> everyone is using these...can/how could u use these


Both these links took me to a page on ceiling fans.


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## metfan581 (Aug 19, 2005)

well one is the spiral and one had 2 "U" shape bulbs


thanks for all your help


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## DarkCobra (Jun 22, 2004)

Hmm, the 2 U-shaped bulbs are probably joined - making one bulb. Same as the spiral, just a different shape.

Of course, we'd have to dissect one to know for sure.


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## metfan581 (Aug 19, 2005)

DarkCobra said:


> Hmm, the 2 U-shaped bulbs are probably joined - making one bulb. Same as the spiral, just a different shape.
> 
> Of course, we'd have to dissect one to know for sure.



thanks for all your help.


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## metfan581 (Aug 19, 2005)

*mounting*

how would you mount the bulbs?
are there such things "end clips"..(something to put at the end of the bulbs?)


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## DarkCobra (Jun 22, 2004)

Yes. Obviously if you're just replacing the ballast on an existing light you don't have to worry about such things. 

But it sounds like you're interested in building from scratch.. You're looking for bulb holders, which lock the bulb in place and supply the electrical connections. I've found them for T8 fluorescents at Home Depot. You can also try McMaster-Carr (www.mcmaster.com) and search for "fluorescent light bulb holder". They supply holders for T12, T10, T8, T5.

That's all I have off the top of my head.


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## sukebe (Nov 6, 2004)

So how are the lights doing? Still running?

Would this be a good alternative to the HOT and buzzy, magnetic, 2-pin AHSupplies ballasts I have?


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## fish_lover0591 (Nov 11, 2006)

I will definetly try this with some cheap 99cents 15 watt bulbs here are some pics.


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## Wasserpest (Jun 12, 2003)

sukebe said:


> So how are the lights doing? Still running?
> 
> Would this be a good alternative to the HOT and buzzy, magnetic, 2-pin AHSupplies ballasts I have?


I am using them in different configurations, to drive 2' T5 bulbs, 18W PC bulbs, 15W T8 bulbs, and others. Works great.

One thing you have to be aware of is the wattage, it doesn't necessarily equal what the spiral bulb has printed on it, for 2 reasons - 1) it might be stated incorrectly (I bought some "30W" labeled bulbs in the $-Store and they are actually drawing only 10W) and 2) the ballast might behave differently when you connect it to a diffent kind of bulb.

It's not as easy as DarkCobra stated in the OP... where you take a 23W bulb ballast, connect it to a 15W bulb, and it is overdriven 50%. I find that most bulbs are actually underdriven, how severely depends on the ballast. Using that 15W T8 bulb, I have a 23W bulb ballast that yields about 12W, and a 26W ballast that yields about 14W.

I am going to try and see what happens when you connect a 13W PC bulb to it, and report back. You are right, it would be an interesting experiment to replace the rather hot AHS ballasts with a cool screw-in ballast, remains to be seen what the resulting wattage is. Project for the weekend.:thumbsup:


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## Wasserpest (Jun 12, 2003)

Wasserpest said:


> I am going to try and see what happens when you connect a 13W PC bulb to it, and report back. You are right, it would be an interesting experiment to replace the rather hot AHS ballasts with a cool screw-in ballast, remains to be seen what the resulting wattage is. Project for the weekend.:thumbsup:


Well... nothing happened. 

The bulbs didn't fire. Maybe they need a special ballast... the PC bulbs I used successfully all had 4 pins, these 13W bulbs have only two.


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## sukebe (Nov 6, 2004)

Awww... I was looking forward to you reporting back with fantastic results! 

Anyway, looks like he got it to work with a two pin lamp, but I don't really understand the principle behind what he did.



hyunbaw said:


> Hey,
> 
> Great idea. My eclipse 12's light broke and so I tried replacing the ballast, and it worked! Since the old ballast was encased in epoxy, I just had to saw that part off and throw it away. I cut and kept the power cord though.
> 
> ...


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## Wasserpest (Jun 12, 2003)

Heh, I don't understand it either... Yes, if you take the bulb apart, two leads are connected to some sort of capacitor, and a glass thing, not sure if it is a fuse, or a starter or something.



> you connect the INNER two leads TOGETHER and simply use the outer two leads. I opened up my used-up 2pin bulb to make sure, and basically I saw 4 leads. The inner two leads were connected together with a safety fuse in between, and the outer two leads were connected to the pins.


Did he short the "inner" two leads then? Maybe it would work if you remove the capacitor and the other thing, route the two previously connected wires outside and connect all 4 wires to the ballast. Maybe I need to play around a little more, but I don't really want/have to open up the bulb in order to make that work.


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## Aquamanx (Sep 28, 2006)

I tried it with a 15 Watt T8 Bulb this weekend, it didn't work for me. The Ballast must have been bad too. I noticed the Bulb had a black spot on it, so, I figured it should be all set. But, it didn't work... I'll have to try it again, seeing the original Ballast is gone. I need a new one in there anyway.

Steve X.


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## jamesd1343 (Feb 5, 2010)

hyunbaw said:


> Hey,
> 
> Great idea. My eclipse 12's light broke and so I tried replacing the ballast, and it worked! Since the old ballast was encased in epoxy, I just had to saw that part off and throw it away. I cut and kept the power cord though.
> 
> ...


just got an eclipse12 and ordered an actinic/daylight combo for the stock hood (13w)..based on whats above can i crack open a 23w household fluorescent and use that ballast with my new bulb to up the wattage? hyunbaw didnt specify what ballast he used ie same wattage or higher but i thought the purpose here was to increase the output.


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## DarkCobra (Jun 22, 2004)

jamesd1343 said:


> just got an eclipse12 and ordered an actinic/daylight combo for the stock hood (13w)..based on whats above can i crack open a 23w household fluorescent and use that ballast with my new bulb to up the wattage? hyunbaw didnt specify what ballast he used ie same wattage or higher but i thought the purpose here was to increase the output.


Hey, I remember this thread! 

Apparently it's not that simple.

My ballast did overdrive my bulb, but by how much I couldn't tell; back then I didn't have useful test equipment other than my eyes.

But Wasserpest reported that with a 15W bulb, he got only 12W from a 23W ballast, and 14W from a 26W ballast.

So it's unknown exactly how much power you will get from any bulb and ballast combination. Given my recent experiments with another ballast (search for "dimming fluorescent ballast"), I tend to think that Wasserpest's result is more common, and the bulb will be driven below the ballast's normal wattage rating.

I still think these ballasts can be useful for replacing broken, loud, or flickery ballasts, especially if you get them for free from spiral lights with burnt-out bulbs. But I wouldn't suggest tearing apart a perfectly good spiral light in the hopes of overdriving another bulb; unless you're willing to sacrifice the spiral light for the sake of experimentation, and despite the possibility of failure.

As always, post any results!


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