I've got this transformer.....check it out!

[mpmarino]

Please guys, project ideas are welcome...

I found this thing in a telecom power supply my company was surplusing. It's gotta weigh 70 pounds..AT LEAST! The power supply was 'conservatively' rated at 60a 52v. I am assuming this thing can do 3KVA without breaking a sweat.

I was playing with the primaries today and I am happy to say I've got a few options. The secondaries are center tapped. As a bonus the PS had 4 38000uF 60 volt caps! I can get any of the following all before rectification:

20.5v + 20.5v
23.3v + 23.3v
39.8v + 39.8v

I wouldn't mind building a 4 channel version of ......

This would be for my line arrays presently under construction ..4 ohms on the tweets..6 ohms on the mids. Whadya think of a 4 channel Aleph or Aleph-x. I can pretty much get all the heat sink I need so that's no worry. Maybe a class a/b on the higher voltages...or maybe an Aleph on the higher voltages? ...is that too high for the Aleph?

I feel like I have a LOT of potential here. Any ideas?

[paulb]

Do you know what the current rating of each of those secondary arrangements are? The lower voltage arrangement, (especially if it has more current than the others) would be best for a Class-A.
Better start looking for heat sinks.

[mpmarino]

I am purely guessing at all specs. I just know what the device it came from was capable of. The wire on the secondaries is ..in my estimation..8ga. You can barely bend the cable with 1 hand! As I look at this transformer..it just looks 'larger than life' to me.

[Nelson Pass]

Looks to me like you can build any kind of killer Class A
you want.

[rcavictim]

I pulled apart some telco battery plant (48V) chargers years ago and got three double-C core xfmers out of each one much as you describe except the primary was 208-230 volts with several taps.
I made a very nice portable arc welder with one and later added a second xfmer in parallel for more welding current. Mine have faraday shielded primary or secondary windings which would be a nice touch in an audio amp application. I don't know what anyone at home would need with that much audio power for though.

[azira]

Woww, looks like a whole lot of iron for a line array. I'd love to see what kind of amp you hook it up to
--
danny

[mpmarino]

RCAvictim,

Hmm, your probably right. No-one in his right mind would 'need' that much power for home use. In fact, I don't even need this computer I am sitting at!


..............so what the heck, why not take it all the way!


Marc

P.S. The thing is so heavy, I may one day call myself "transformervictim".

[Super_BQ]

I come across these large types of transformers all the time. I normally find them in these huge refridgerator size rectifiers for telecommunications. The units are very old and because of the shape and appearance of these transformers, I don't even bother looking at them. Instead, what I do take are the rather large size heatsinks inside these rectifiers. Sometimes I get arrays of CG type capacitors.

Another thought is the chemicals used in these transformers. PCBs is known to be cancerous - only if the transformer is old enough.

With the measured voltages, my guess it could make a good 25w/ch Son of Zen amp.

BQ

[markp]

No PCBs in that type of transformer. PCBs are in the encased type of transformer.
I've got a similar unit that has wire that looks like bussbar, about 3mm thick and 5mm wide! It weighs at least 60lbs. and has dual primaries and dual secondaries of 60VCT.

[Circlotron]

I think PCB's (polychlorinated biphenyls) are/were in old-type transformer oil. Some kinds of oil-filled paper capacitors too.