Finished 12V equipment.

[margusten]

Hello,

I made second windmill controller using old computer PSU parts:

Computer PSU has nice power connector, You can use it after some modification:

Picture of test and tuning, I have this big analog ammeter(running to 30A), adjustable PSU and multimeter to measure voltage. I found multimeters can show wrong amperage at currents more than 3A because thin cables used.

4X40W car stereo sounds good in my room. However big condensators needed to compensate long 12V wire run from garage.

Latest best found is this lamp grabbed from old scanner, working on 12V. It makes more light than ordinary 12V 8W working light.

You can see from this picture also my windspeed meter, reading lamp and battery status monitor.

From another scanner I found this, inverter working from 28V and I can't find out how to turn CFL light on. So all scanners are not gold mines.

Wondering can I use old PSU supply transformer in CFL 12V inverter?

Probably not, I have to rewind this thing.

Who has made this sucessfully, can write about this.

BR,

Margus

[wooferhound]

Hey

Nice going

Your stuff reminds me of my stuff

except I'm all Solar power right now

[Opera House]

I've saved one of those scanner lamps.  Have wondered how long they would last with continuous use.  I buy a lot of 12V inverters and pull the H bridge fets out of the less desirable ones to fix others.   That leaves me 12V to 140 V inverters.  I have found that the GE CFL lamps with electronic ballast work fine on 140V DC.  Several CFL lights in my shed are switched on from the "neutral" side.  An isolating diode is also connected to each switch to minus.  That turns on a small 12V relay that turns on the inverter.  An easy control setup to turn on lights and inverter automatically.  Not exactly code but I can see that is not an issue with you.  That would work with your little inverter.  Want to mention for the benefit of others not to run electronic ballast CFL lamps directly off 40KHZ, the diodes won't like it.

[richhagen]

Commanda has made a few flouro inverters from old psu tranformers and posted about it here:  http://www.fieldlines.com/story/2007/12/13/05649/929

Rich

[TomW]

Margus;

Always fun to get useful parts from throw aways.

One mans junk and all that ..

Great stuff.

Thanks for sharing.

Tom

[Madscientist267]

Getting the current right on a fluorescent is really the hard part. Too cold or too hot and the bulb ages quicker than it should.

Quick and dirty involves a simple hartley oscillator (many scanners use this already), and then play with the value of the coupling capacitor on the output to adjust current to the right values. There are several factors that determine the right choice, so I can't really go into all that here. Oscillator Frequency, bulb voltage and current requirements, etc. I usually play around with small values (about 0.1uF for many cold cathode lamps, but CFL will likely be a little higher).

The basics of a hartley: http://en.wikipedia.org/wiki/Hartley_oscillator

The other alternative is rewinding the original transformer, if you're feeling froggy enough.

Steve

[divemaster1963]

hey i see you are using the old auto jumpbox. have you looked at the charging part yet? I was trying to figure out how to use it to charge my battery bank sence has a automatic shutoff when the batteries reach 14.6 volts. I can not figure out how to wirer it to go to a dump instead of just shuting off.

Can you heop me with this? I'm weak at wireing.

[margusten]

Hi,

I made this. Old computer PSU transformer CFL inverter working now.

Magic thing was used choke from broken 220V CFL inverter. You have to put this in series of CFL lamp and use small capacitor like in original 220V CFL inverter.

This PSU transformer has primary windings for 3,3V 5V and 12V. Best to use 12V windings but then CFL has starting problems:

May be good idea is add a starting switch using 5V winding, after a few seconds when CFL bulb is hot and then switch to 12V winding.

Always use ampermeter to measure current first, I've seen 7A and this tiny bulb shines so bright it can explode after some minutes.

BR,

Margus

[margusten]

Hello,

I've not using this charging part of this auto jumpbox.

However it is connected and this red led starts to shine when battery voltage hitting 14V. I guess it's working too but limited somewhere 2A charging current. Tiny diodes inside.

[margusten]

Shining good 12V 0.6A like original at 220V when bought.

Original circuit worked for few years and stopped. Probably electronics fault as always. It is second life for this bulb.

BR,

Margus

[commanda]

We need to see the circuit. I know you've seen my 24 volt circuit using a pc psu transformer because it was in a photo you posted several days ago. Someone was emailing me, trying to get it working on 12 volts, but I don't think they ever succeeded, and I haven't had time to pursue the matter.

Amanda

[Opera House]

I would think an alternate method to the choke and capacitor to limit current would be to monitor current.  Use a sense resistor in the return path of the lamp, filter it, and use that voltage to control the switching regulator.  With the screw in lamps with the electronic ballast less than $150 each, I haven't had a need to drive the tubes directly.  As I said before, these self contained electronic ballast lamps run fine on 140V DC.  That can easily be supplied by these old power supply transformers.

[margusten]

Hello,

I have to work on this circuit little bit more.

It has starting problems on 12V.

When it is ready I will show You.

BR,

Margus