Anyone figure these out yet. The main type I seem to see is black and white 16 gauge are 120 in. When checking the voltages on the secondaries which are 4 wires.
3 are 15 gauge colored brown yellow and red. Then there is a smaller 18 gauge red wire.
Voltages at 125 volts (my house voltage) are;
Brown to yellow 16volts
yellow to either red 7.7
brown to either red 7.7
red to red 0
That would be a 7.7-0-7.7 transformer with an extra ground?
Just about useless.
Thanks
3 are 15 gauge colored brown yellow and red. Then there is a smaller 18 gauge red wire.
Voltages at 125 volts (my house voltage) are;
Brown to yellow 16volts
yellow to either red 7.7
brown to either red 7.7
red to red 0
That would be a 7.7-0-7.7 transformer with an extra ground?
Just about useless.
Thanks
check that they are not auto-transformer types, you can make battery chargers out of those..or a bench psu..
How these work...
- Thick red winding is connected to +12V battery positive. Thin red winding is used for who knows what.
- Yellow/brown windings are alternatively connected to battery negative, at 60Hz. Duty cycle is less than 50%, typically 35% or whatever gives 120VAC RMS on the output.
- Result is a square wave of about 180V peak coming out of the AC windings. With resistance/inductive loss this ends up being about 170V, about the peak AC voltage you normally get from a wall.
- When 120V is driven into the AC side of the transformer, the body diodes of the switching FETs conduct and charge the battery.
- Thick red winding is connected to +12V battery positive. Thin red winding is used for who knows what.
- Yellow/brown windings are alternatively connected to battery negative, at 60Hz. Duty cycle is less than 50%, typically 35% or whatever gives 120VAC RMS on the output.
- Result is a square wave of about 180V peak coming out of the AC windings. With resistance/inductive loss this ends up being about 170V, about the peak AC voltage you normally get from a wall.
- When 120V is driven into the AC side of the transformer, the body diodes of the switching FETs conduct and charge the battery.
Thanks Gmarsh that was way more infor then I was looking for but now I understand how it works.
I was hoping I could use these for a small amp since I have 1/2 a dozen of these things and they are considered obsolete at the company I work for and was told to get rid of them in a friendly environmental way.
I strip the UPS's for recycle. Batteries go to a battery place, circuit boards go to a place that recycles them and if they are metal cases to the metal scrap yard, plastic cases, presently in the trash since I haven't found any place that recycles plastic.
I haven't found a place here in central Ohio that takes transformers and haven't figured a quick and easy way of separating the copper from the metal.
Nice trannys just can't think of a use for them.
I was hoping I could use these for a small amp since I have 1/2 a dozen of these things and they are considered obsolete at the company I work for and was told to get rid of them in a friendly environmental way.
I strip the UPS's for recycle. Batteries go to a battery place, circuit boards go to a place that recycles them and if they are metal cases to the metal scrap yard, plastic cases, presently in the trash since I haven't found any place that recycles plastic.
I haven't found a place here in central Ohio that takes transformers and haven't figured a quick and easy way of separating the copper from the metal.
Nice trannys just can't think of a use for them.
To strip the copper, get a hacksaw and cut through the windings on one side of the transformer, all the way to the core. Wedge a crowbar between the windings and core on the other side, and pry the windings out.
Don't have many other suggestions. If you can get the secondary off and keep the primary intact, you could wind a new secondary of a different voltage.
Don't have many other suggestions. If you can get the secondary off and keep the primary intact, you could wind a new secondary of a different voltage.
Watch for losses with a doubler.
The losses are roughly proportional to the power of the multiplier ratio.
no doubler = [1+X]-1 = X,
doubler = [1+X]² - 1
tripler = [1+X]³ -1
The losses are roughly proportional to the power of the multiplier ratio.
no doubler = [1+X]-1 = X,
doubler = [1+X]² - 1
tripler = [1+X]³ -1
I took 3 more UPS's apart last night. 2 were plastic case APC units, massive transformers (4lbs 6 oz) in them the CT were 7.8 but these had another secondary with a 4 amp fuse and they measured 19.2 volts but no center tap 🙁
430-2060 Class B 130 degrees C LEI-4 plus factory numbers is the writing on them
The other unit was an APC metal case 320 it had the standard 7.8-0-7.8 transformer. It wieghed in at 4 lbs 12 oz.
So I did a google search for 16 volt audio chips and found a couple of low wattage units
Electronics 101 - Fundamentals of Electricity - Lesson 68 - Microchips describes an LM741 and I also found a TDA 1521 but haven't found a data sheet for that.
Neither of these chips would even come close to the amperage draw these transformers could put out.
Since I have 2 transformers that appear to be identical and a 50 TDA 2050 chips I may try a dual power supply this winter if I find time. Till then in a box they go.
Thanks for all your help.
Interesting that those APC's use these to turn 12v to wall outlet voltages, the circuit board looks extremely complicated. I have unsolder-ed a couple of coponents and the solder they use is very hard
430-2060 Class B 130 degrees C LEI-4 plus factory numbers is the writing on them
The other unit was an APC metal case 320 it had the standard 7.8-0-7.8 transformer. It wieghed in at 4 lbs 12 oz.
So I did a google search for 16 volt audio chips and found a couple of low wattage units
Electronics 101 - Fundamentals of Electricity - Lesson 68 - Microchips describes an LM741 and I also found a TDA 1521 but haven't found a data sheet for that.
Neither of these chips would even come close to the amperage draw these transformers could put out.
Since I have 2 transformers that appear to be identical and a 50 TDA 2050 chips I may try a dual power supply this winter if I find time. Till then in a box they go.
Thanks for all your help.
Interesting that those APC's use these to turn 12v to wall outlet voltages, the circuit board looks extremely complicated. I have unsolder-ed a couple of coponents and the solder they use is very hard
I salvaged 4 transformers from APC BackUPS 500's and two from BackUPS 650's. The part numbers are 430-2002.11 and 430-2003A.11. Primary wires were higher gauge white/black, and secondary wires were lower gauge white/violet/yellow, with violet being the center tap. Core dimensions are 1.25D x 3.125H x 3.75L and 2.0D x 3.5H x 4.125L, in inches, respectively. Core area is D dimension times 1.25.
I ran resistive load tests on the secondary, with line voltage today at 120.8 volts (60Hz).
The smaller unit had a no-load voltage of 16.5 volts, and under load the voltage dropped linearly with current until I was drawing 14.9 amperes at 14.5 volts (216 volt-amps). Effective secondary series resistance is about 0.165 ohms. At 90% of no load voltage, the current was 12.2 amps at 14.75 volts, or 180 volt-amps, and this is what I expect to be the rating of this unit.
The larger unit had a no-load voltage of 17.1 volts, and under load the voltage dropped linearly with current until I was drawing 18.3 amperes at 15.9 volts (290 volt-amps) (93% of no-load). Effective secondary series resistance is about 0.070 ohms. Extrapolating down to 90% of no load voltage, the current was 12.2 amps at 14.75 volts, or 360 volt-amps, and this is what I expect to be the rating of this unit.
Both units were dead quiet and vibration-free at no-load, full rated load and beyond. Lack of noise indicates to my mind that core saturation should not be a problem, at least with resistive loads. Rectifier/capacitor input filter tests will be forthcoming.
I soaked the units for about 30 minutes at 216 watts for the smaller and 290 watts for the larger, and measured the temperature rise with an infrared thermometer to be about 20 degrees fahrenheit. I'll do a longer soak later, (and at full load for the larger unit) and report the findings.
Preliminarily, these look like good solid performers, especially given the cost (free!) I intend to use them in a tube OTL circlotron. The larger unit will supply the output triode heaters (2 x 6.3V @ 10A for 8 6AS7s, or 126 watts), with possibly small ballast resistors to reduce the heater voltage a tad, and drive the secondaries of two of the small units to develop 120-140 volts dc after rectification for the floating supplies for the output stage. Simulations are underway as we speak.
I ran resistive load tests on the secondary, with line voltage today at 120.8 volts (60Hz).
The smaller unit had a no-load voltage of 16.5 volts, and under load the voltage dropped linearly with current until I was drawing 14.9 amperes at 14.5 volts (216 volt-amps). Effective secondary series resistance is about 0.165 ohms. At 90% of no load voltage, the current was 12.2 amps at 14.75 volts, or 180 volt-amps, and this is what I expect to be the rating of this unit.
The larger unit had a no-load voltage of 17.1 volts, and under load the voltage dropped linearly with current until I was drawing 18.3 amperes at 15.9 volts (290 volt-amps) (93% of no-load). Effective secondary series resistance is about 0.070 ohms. Extrapolating down to 90% of no load voltage, the current was 12.2 amps at 14.75 volts, or 360 volt-amps, and this is what I expect to be the rating of this unit.
Both units were dead quiet and vibration-free at no-load, full rated load and beyond. Lack of noise indicates to my mind that core saturation should not be a problem, at least with resistive loads. Rectifier/capacitor input filter tests will be forthcoming.
I soaked the units for about 30 minutes at 216 watts for the smaller and 290 watts for the larger, and measured the temperature rise with an infrared thermometer to be about 20 degrees fahrenheit. I'll do a longer soak later, (and at full load for the larger unit) and report the findings.
Preliminarily, these look like good solid performers, especially given the cost (free!) I intend to use them in a tube OTL circlotron. The larger unit will supply the output triode heaters (2 x 6.3V @ 10A for 8 6AS7s, or 126 watts), with possibly small ballast resistors to reduce the heater voltage a tad, and drive the secondaries of two of the small units to develop 120-140 volts dc after rectification for the floating supplies for the output stage. Simulations are underway as we speak.
I had a APC 1500VA that I took the transformer out of. There was a 11.5 Vac, a 76v, 32v and a 13v output. I then checked to see which wires were connected together and found that all of them but the 11.5 were all attached together. I figured out what wires to put 120V ac into but 11.5 @50 Amps isn't much good for anything but a battery charger so I disassembled the transformer plate by plate and took off the secondary 11.5 which gave me almost 1.7lbs of wide copper foil. Found out that the primary were 4 sets of different awg wire soldered together so I stripped off the whole thing and re-wound primary with a single awg salvaged off an old 1976 non rebuildable mobile trailer 12V transformer.
Now I'm just awaiting a project that I can rewind this monster for. 😀
Now I'm just awaiting a project that I can rewind this monster for. 😀
never thought about tube heaters, one thing for sure with that iron in them no thief is going to run very far 🙂
I had one of those about 400 watt and I still have 1000watter.
I made high current regulator for it that was variable out of an opamp and 4 paralleled 2N3055's.
It would produce about 50amps at 9v worst case.
I hooked it to a small spool of 22ga. 4 conductor telephone wire and a I also tried a medium sized spool of speaker wire ( infact I tried every spool of wire I had) and it created enough magnetic flux to pick up a few heavy wrench's and stuff without even having a iron or steel center core!!!
It would attract a bottle cap at well over a foot away!!
I had a 30 step LED baragraph display at .5v per step to indicate the output voltage.
You could use 2 or 3 of those to power a pair of Aleph J or X class A Nelson Pass amplifiers.
I had a lot of fun with mine and the applications are endless!!!
jer 🙂
I made high current regulator for it that was variable out of an opamp and 4 paralleled 2N3055's.
It would produce about 50amps at 9v worst case.
I hooked it to a small spool of 22ga. 4 conductor telephone wire and a I also tried a medium sized spool of speaker wire ( infact I tried every spool of wire I had) and it created enough magnetic flux to pick up a few heavy wrench's and stuff without even having a iron or steel center core!!!
It would attract a bottle cap at well over a foot away!!
I had a 30 step LED baragraph display at .5v per step to indicate the output voltage.
You could use 2 or 3 of those to power a pair of Aleph J or X class A Nelson Pass amplifiers.
I had a lot of fun with mine and the applications are endless!!!
jer 🙂
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I would be interested in seeing how you made the high current regulator out of an opamp and 4 paralleled 2N3055's. I have a few 2n3055.
I had the schematic somewhere in my archives and I have been trying to find for sometime now.
It was different than most designs.
It was the first working circuit that I built and designed using CircuitMaker back in 2002.
It was proof as to how accurate the program really is.
I used an opamp that drove an IRF511 FET and it supplied the current to feed the 4 X 2N3055's.
I used a LM7815 for a reference and to power the opamp.
I had everything heatsinked with fans including the high current bridge rectifier.
The thing was heavy duty and never broke a sweat under heavy loads for very long periods of time.
There was about 70,000uf or more worth of filter caps in it.
It got lost in my move from Florida to Michigan or else I would still have it and be using it today.
I have been wanting to venture into Class A power amps lately and have been thinking about building another one using the 1000watter that I have from a blown APC unit (Bad Control Board).
There are many similar circuits that can be found on the web that use a LM317 type variable regulator and paralled 2N3055's as well opamp driven designs.
I will try to find a few links for you.
Many use the PNP version 2955's but 3055's can be used as the configuration is only slightly changed and with maybe one added smaller driver transistor for the 3055's base's.
I wasn't able to get a 0v output out of it as that was the goal (0v to 19V or so), But I got it down to like .2V to .3V output in its 0V state.
jer 🙂
It was different than most designs.
It was the first working circuit that I built and designed using CircuitMaker back in 2002.
It was proof as to how accurate the program really is.
I used an opamp that drove an IRF511 FET and it supplied the current to feed the 4 X 2N3055's.
I used a LM7815 for a reference and to power the opamp.
I had everything heatsinked with fans including the high current bridge rectifier.
The thing was heavy duty and never broke a sweat under heavy loads for very long periods of time.
There was about 70,000uf or more worth of filter caps in it.
It got lost in my move from Florida to Michigan or else I would still have it and be using it today.
I have been wanting to venture into Class A power amps lately and have been thinking about building another one using the 1000watter that I have from a blown APC unit (Bad Control Board).
There are many similar circuits that can be found on the web that use a LM317 type variable regulator and paralled 2N3055's as well opamp driven designs.
I will try to find a few links for you.
Many use the PNP version 2955's but 3055's can be used as the configuration is only slightly changed and with maybe one added smaller driver transistor for the 3055's base's.
I wasn't able to get a 0v output out of it as that was the goal (0v to 19V or so), But I got it down to like .2V to .3V output in its 0V state.
jer 🙂
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7V rectified will be about 10VDC. It can be used to energize a TDA2006 with about 6-7Watts into 4R
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