# Putting an Unknown Transformer to good use

#### bhvm

Joined Jul 16, 2009
53
Hello Friends,
Help me put this beautiful transformer to Good use. It was pulled out from an Computer UPS. Simple model, Rated at 500VA, Square wave.It Used a 12v 8AH battery for storage. I have attatched pics for your reference.

I would be interested to know the function of this transformer in its original Application. I guess its for charging the battery. But will it also "up convert" the power from battery? Are so many taps for voltage stabilization? Does it provide multiple outputs for various solid state components/LEDs?
What would be the possible Input/Output Voltages and Amps?

Assumed Secondary-
Thick winding. Continuty meter shows perfect contunity among 3 terminals. I think there are 2 coils but the red wires are soldered together (seen in pic) so acting as single coil with Center tap. Is this correct?
There are some mysterious orange wires showing contunity among themselves but nowhere else (What are these for?) . Is this THE secondary?

Assumed Primary-
Oh boy! So many wires!
The Blue and Green ones among far right is a mysterious/Seperate coil. Just showing continuty among self, nowhere else. The handful of wires other than these show perfect continuty among each other, any way , any wire.

So there you go,
I'm more interested in step down use to run LEDs etc (I have most of my house converted to LEDs)

Thanks.

#### bhvm

Joined Jul 16, 2009
53
Reserved for pics

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#### Kingsparks

Joined May 17, 2011
118
Hello yourself bhvm.

Boy, that is an open question. No pictures showed up but I am not sure how much help they would be anyhow. The transformer from a UPS could be used to both charge the battery but it also has to provide the output for the UPS.

Look the thing over and see if there is a name of any sort and any numbers that might be part numbers. Most transformers will have them although don't be surprised if you don't find anything.

In that case it would be a guess as to what is what.

I would not, not, not recommend trying to use it until you find out something, a lot more then you know now. Good luck.

Roland

#### bhvm

Joined Jul 16, 2009
53
Hello yourself bhvm.

Boy, that is an open question. No pictures showed up but I am not sure how much help they would be anyhow. The transformer from a UPS could be used to both charge the battery but it also has to provide the output for the UPS.

Look the thing over and see if there is a name of any sort and any numbers that might be part numbers. Most transformers will have them although don't be surprised if you don't find anything.

In that case it would be a guess as to what is what.

I would not, not, not recommend trying to use it until you find out something, a lot more then you know now. Good luck.

Roland
So here are your pics mate, hope theyre mighty useful.
First one is Secondary, then primary, Third one is a secondary close up.

#### Kingsparks

Joined May 17, 2011
118
Hi bhvm.

As I mentioned earlier, the pictures do not help.

I take it you could not find any numbers? If you know someone who works as a technician you could try asking him/her/it, whatever to check it out. They might be able to help but as is, I sure can'r. Sorry.

Roland

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#### PackratKing

Joined Jul 13, 2008
847
There is a small truckload of things that can be done with a transformer of that size.

Research into a units' windings / leads must be done to determine how to utilize them for any potential project... since the heavy guage windings are actually a backfed primary, driven by an inverter, powered by the battery in a UPS unit...

I was given a procedure to analyze and utilize virtually any/all transformers by another party on these forums, which I am willing to share.

#### Kingsparks

Joined May 17, 2011
118
There is a small truckload of things that can be done with a transformer of that size.

I was given a procedure to analyze and utilize virtually any/all transformers by another party on these forums, which I am willing to share.

Hi PackratKing,

I don't know about anyone else but I would be interested in such a procedure. I don't think I have any unidentified transformers currently but there have been times I had to do it the hard way.

Thanks!
Roland

#### MrChips

Joined Oct 2, 2009
19,383
Step 1: Knowing where the transformer was installed and its function is a good starting point. Knowing that it was used to step down AC line voltage to a lower voltage is useful information.

Step 2: Get out your ohmmeter and measure continuity and resistance across all combinations of windings AND metal frame.

Step down primaries would have finer wire and higher resistance.
Secondaries would have courser wire and lower resistance.

Primaries are usually designed for different countries, e.g. 120VAC and 240VAC.
Primaries may be one winding with multiple taps or two or more windings.

Secondaries may be single winding, center tap, multiple tap or multiple windings.

A ground wire may be present.

#### Kingsparks

Joined May 17, 2011
118
MrChips.

Thank you, that's pretty much the way I always started, add an isolation transformer and a verac and I can pretty much figure out whats what.

I'm always open to new ideas though and now I'm retired I don't have all the test equipment I did at one time.

When I sold my company most of that went with it.Still have my scope and a few things but like me, there all old.

Roland

#### Evil Lurker

Joined Aug 25, 2011
116
Having tinkered around with one myself, I'm gonna throw it out there that the two thick black wires is your main secondary winding, and the blue wires are a center tap. Also gonna guess that the two orange wires near each other are your primary coming in off the mains or another secondary winding meant to power whatever on the controller PCB. All the other wires on the other side are probably in fact your primary, and I'm also gonna guess that it is multitapped for different input voltages, maybe three phase? I'm not that good.

Buuuut, if you wanted to reuse the transformer, and can figure out your primary and secondary windings, you might wanna just take the blue (connected to the red wires) solder them together and hook it up to a full wave rectifier and see what sort of voltage you get. I think the last one I messed with put out some 11v when rectified as a center tap secondary, and like 22v when hooked to a bridge rectifier.

To convert it to a useful voltage, get yourself a couple computer grade caps (Jameco's store on Ebay had a deal a while back on some 33,000uF caps for like $8, BGmicro I think has them from time to time too for cheeeap) a few LM723's and a couple 2N3055 pass transistors and look up some circuit designs from some old Astron or Pyramid (?) power supplies. Thread Starter #### bhvm Joined Jul 16, 2009 53 Hi bhvm. As I mentioned earlier, the pictures do not help. I take it you could not find any numbers? If you know someone who works as a technician you could try asking him/her/it, whatever to check it out. They might be able to help but as is, I sure can'r. Sorry. Roland No markings , No Stickers. I'll try playing aroud with 9vAC and see. Thanks Thread Starter #### bhvm Joined Jul 16, 2009 53 Having tinkered around with one myself, I'm gonna throw it out there that the two thick black wires is your main secondary winding, and the blue wires are a center tap. Also gonna guess that the two orange wires near each other are your primary coming in off the mains or another secondary winding meant to power whatever on the controller PCB. All the other wires on the other side are probably in fact your primary, and I'm also gonna guess that it is multitapped for different input voltages, maybe three phase? I'm not that good. Buuuut, if you wanted to reuse the transformer, and can figure out your primary and secondary windings, you might wanna just take the blue (connected to the red wires) solder them together and hook it up to a full wave rectifier and see what sort of voltage you get. I think the last one I messed with put out some 11v when rectified as a center tap secondary, and like 22v when hooked to a bridge rectifier. To convert it to a useful voltage, get yourself a couple computer grade caps (Jameco's store on Ebay had a deal a while back on some 33,000uF caps for like$8, BGmicro I think has them from time to time too for cheeeap) a few LM723's and a couple 2N3055 pass transistors and look up some circuit designs from some old Astron or Pyramid (?) power supplies.
Thanks for the input.
If it provides any standard Outputs (12v or 24V) I;ll be blessed! The uses are endless. And I have high hopes for 12v (14v?) output becaused it has hooked up to some 12v Lead acid battery in its dedicated setups.