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AC to AC/DC buzzbox welder conversion - any of these parts suitable? (pix)

I've dismantled what looks to me like a huge (probably 1987 vintage) standby UPS (uninteruptable power supply). looks like it contains a nice big rectifier bridge (with four diodes and 2 'unknown' black things on it). also on the same unit are two small mini-circuit boards, which serve 'function unknown'. anybody with ANY clues whatsoEVER welcome to respond :-) becasue I'm in a 'zero visibilty fogbank' here....

here it IS:

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also found within same unit a huge transformer, which might become (after being partially unwound then part REwound) the core transformer of a 'homebrewed' welding high frequency converter ('later' :-). comments appreciated as to wether or not some/any, or none of these parts could be suitable for purposes intended (mainly the AC to AC/DC miller thunderbolt220 volt buzzbox conversion purpose), and, if that's 'totally unknown without their specs', what test procedures I could follow to determine wether or not these parts are a. in fact still 'good', and/or b. how their specific capacities,'specs', or ratings can be determined? (when not found on net)

after circuit design etc I intend to house the AC/DC "adapter" in a seperate (probably old computer) case.

I'm not even sure IF (one of the components pictured) *IS* a bridge rectifier, jus' for starters :-/

thanks for educating me

box

ps-some of the threads below gave me this hairbrained idea ;-).

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change your AC welder to AC/DC- *how*

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Tig-conversion ideas for buzzbox to AC/DC/TIG box....

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thread on AC/DC diodes/chokes and bridges

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SCR to change AC to AC/DC welders...maybe

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maybe use 150 amp diodes in the bridge

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built a BULLETPROOOF bridge rectifier....

and some of the "high frequency unit - build it yourself idea" threads:

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re hi frequency DIY

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Arc Stabilizer-homemade DIY high-frequency ADAPTER++++++++++++++++++++++++++

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"arc starters"-thread

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coil-Construction, Best Links (tesla coil primary circuits and "high frequency adapter welder" boxes are VERY similar, components-wise, according to some threads)

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Basement-obtaining tesla parts VERY CHEAPLY-how

Reply to
dave
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The "button" things are TO-3 cased transistors or diodes. Most likely transistors.

I don't know what the boards do, but I know I want them >:)

The wire looks pretty comparable to what I'd expect a transformer that size to use for 120 or 240V operation... so you might be able to use it as-is.

Depending on how much efficiency (dissipated power, temp rise) you can tolerate in your transformer, it might be worth a few kVA. Just a photo, but looks like the core (laminated iron) is at least three or four inches thick (stack), by about as thick in the center limb (the width where the wire is wrapped around). The wire seems to be anything from #8 to #12 AWG on the secondary, with heavier stuff on the primary. (I'm assuming it was used as an inverter, so the lower voltage higher current winding is primary.)

Tere's gotta be a diode somewhere in there, for charging the batteries.

Tim

-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @

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Reply to
Tim Williams

Can you make some larger scale photos of the entire unit?

I recently demolished a huge UPS also, and took out 8 very large high voltage capacitors, and sold that on ebay for about $75 net.

I have one also, please take it from me if you want to. :)

I concluded that it was not really worth the time to make a welder out of this.

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I did not see a bridge rectifier on any of your pictures, but it probably is in the UPS. It may be controlled (turned on and off)by some little wires, so, you may need some figuring out.

By the way, I have a 100A 600V 1-3 phase rectifier, that I will list on ebay soon.

i
Reply to
Ignoramus28403

By the way, look for a large heatsink. Your rectifier is likely to be on it.

i

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Reply to
Ignoramus28403

Dave,

To answer a few of your questions,

Yes the 'Silver thingie' and the 'blue thingie' are both medium sized caps.

No those are not rectifiers they are NPN Darlington transistors. I googled the part number "PTC10021" which is printed on them and got several good hits go here for full specs...

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googeling part numbers is a good way to get info, you just have to wade through places that want to charge for spec sheets. The black 'thingies' next to them are heat sensors.

It looks like the only rectifiers are the ones on the mini circuit boards, you are right the round things is a cap, and the long dark thing is a resistor, but the other the long yellow thing is another cap... if you can read the part number on the rectifiers you can probably google up their rating but they look kinda wimpy to me.

I'd say there isn't much for you to use here.

Please take this the right way, I don't mean to flame you, but if you don't know parts like this by sight I'd be worried about you trying to build anything as highpower as a welder...

Dave August

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thread: change your AC welder to AC/DC- *how*

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another thread on AC/DC diodes/chokes and bridges

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using SCR to change AC to AC/DC welders...maybe

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or maybe use 150 amp diodes in the bridge

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thread re hi frequency DIY

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tersla coil-Construction, Best Links (tesla coil primary circuits and

Reply to
Dave August

BTW, it's harebrained. :-)

Reply to
Watson A.Name - "Watt Sun, th

| > box | >

| > ps-some of the threads below gave me this hairbrained idea ;-). | | BTW, it's harebrained. :-)

Are you sure? The meds I've been taking lately...... Definitely fuzzy in there! :)

Reply to
carl mciver

There is no bridge rectifier visible. Nice caps - you'll find the specs written on the side.

I'm puzzled as to how you're going to build the thing. Can you follow the threads you cited to put the thing together?

Ed

Reply to
ehsjr

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