Repairing A Variac

There was a discussion on another group that discovered that 100% of these particular units from one particular run had the Hot and Neutral wires reve rsed by color. When repaired, 30% of them overheated. When returned, the co mpany refused to refund stating that the repair (reversing the wires) voide d the warranty. In a word, China.

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You get what you pay for in electrical equipment. Shoddy/defective goods ca n kill. And sometimes do.

Peter Wieck Melrose Park, PA

Reply to
peterwieck33
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Probably not that bad, but I have to get the exact size magnet wire, and then file it down to be flat for the wiper to contact. The fact that I almost always use it in cut not boost makes just eliminating that part of the winding a viable option.

Reply to
jurb6006

It is not grounded at all. So it must be arcing to the core but there must be another arc somewhere where it is at a lower voltage. It's not looking good. I wonder if it is even worth doing anything with.

And age ? It is old enough not to be grounded. I mean it does not have a 3 prong plug, and neither the cord or the outlet are even polarized.

It is not a spring chicken.

Reply to
jurb6006

a dumpster 30 years ago. "

First of all, while it was given to me it did not come from a dumpster. And you don't know me, don't assume you do. To do so shows willful ignorance a nd bad attitude. And of course the immaturity not to realize it, accept it and change for the better. You want to be an asshole so what. Unless I care what you say means jack shit.

Admit ? So there's something wrong with fixing things ? I think there is so mething wrong with YOU. This is sci.electronics.REPAIR, where the f*ck do y ou think you are ?

Have you ever even seen my work at all ? Do you have cameras on me ? Did yo u have cameras at my bench when I was making $ 34 an hour, setting my own h ours and was pretty much second in command at work ? How can you say anythi ng ? What you do it called talking out your ass around here.

And the FACT that you talk about things you obviously know absolutely nothi ng about brings into question your credibility on everything. But then you' re not known for constructive advice, you only bitch. bitch about thinks yo u don't even know. what does that make you ?

If you don't like me, don't respond. That is unless you do just to hear you rself bitch, which is starting to look like what it is with you.

You might just end up like Slowman, talking to yourself.

Reply to
jurb6006

I would say almost and that is because they are not as useful these days. M ost brownwares today won't turn on at too low a voltage, even though their power supply would regulate. Even audio amps, on which the use of a variac was common, they also won't fire up at too low a voltage. You have to jump out relays n shit like that. Computers will start but the PS is practically considered replace only, except in case of the shit ones with the propriet ary wimpy PSes which are smaller and also fan the processor so you can't us e a standard form factor. And this shit is getting more common because busi nesses want a PC that screws right to the back of the monitor, like in hosp itals these days. Fixing those PSes might make a comeback as people get sic k of paying 4 or more times as much for an inferior product. But again, I t hink in some cases even though they would run on the lower voltage, the mig ht not start.

So it's not surprising not to find them all over the place.

Reply to
jurb6006

For 100 bucks it is worth a crack at fixing. Even if it is cut only.

Reply to
jurb6006

OK - from 20,000 feet, and with over 45 years around electricity, some of i t with a license, if I were to attempt to fix this beast, I would make sure it met *ALL* the proper life-safety requirements. If windings are shorting internally, then the insulation below them is compromised. Fish Paper come s to mind, then dielectric varnish.

If there are any doubts, the device goes off to the salvage yard forthwith. Perhaps I am OK with messing about with unsafe stuff, but I may not be the end-of-the-line.

As Kutztown is at the end of next week, there will be good Variacs a-plenty from an amp or two up to 20 amp monsters, most of them selling for less th an their salvage value. These things are neither scarce nor expensive if on e knows where to look.

I keep two Heathkit IP 5220 Iso-Variacs A small write-up with pictures is a ttached below (not mine).

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Peter Wieck Melrose Park, PA

Reply to
peterwieck33

You get what you pay for in electrical equipment. Shoddy/defective goods can kill. And sometimes do. "

YIKES ! 455 bucks ? Maybe I'll spend more than 5 minutes on it. In fact maybe I'll count the turns and put a micrometer on the wire, see if It can get me some.

If I do all that I will probably upgrade it a bit with a grounded cord and outlet. Maybe get one of those small DVM modules...

Reply to
jurb6006

Kutztown ? Do they have like a mini hamfest type of thing there ?

Reply to
jurb6006

Damn, I sold a couple to cheap! Mikek

But, I didn't have to haul them home!

Reply to
amdx

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Not so mini. A few hundred dealers, 2.5 days, a pretty good auction, fireworks, food, fun and so forth. Twice per year, this will be Kutztown XXXVIII.

I run a vintage radio clinic at the Club Table - diagnosis and basic repairs - for those who wish to learn.

Peter Wieck Melrose Park, PA

Reply to
peterwieck33
[ usual chest beating drivel snipped ]

You really are a legend in your own mind.

--
"I am a river to my people." 
Jeff-1.0 
WA6FWi 
http:foxsmercantile.com
Reply to
Fox's Mercantile

Typical Murphy's law. Got it all apart, fired it up and no sign of arcing.

Do I run it apart forever or paste a picture of myself inside ? (I know the latter might be a scary thought but sometimes more severe measures are required)

Reply to
jurb6006

Go to rec.antiques.radio+phono to find out...it has been on for many a year now.

John :-#)#

-- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games)

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"Old pinballers never die, they just flip out."

Reply to
John Robertson

Nice unit !!

Reply to
Rheilly Phoull

Those are nice, but a bit undersized for what I work on.

So I bought a 20 amp Sola "Harmonically balanced" (four winding) constant voltage transformer. From about 85-145 v it will hold a steady 120 v and a reasonable looking sine wave. I put a three position "center off" switch on the front panel to select "Line Neutral" "Floating" or "Line Ground" for the "neutral" line on the output. Following that, I put a 20 amp Variac wired for 10% boost at max. Then came the metering.

0-150 vac meter, 0-30 amp ac meter, and a 4-wire 3000 watt ac dynomometer or direct reading of the load in watts.

Just for good measure, all the cords, plugs and outlets are rated at 20 amps.

I also have a 2500 watt 400 Hz inverter for working on old aircraft equipment.

If you're going to do something, do it right.

--
"I am a river to my people." 
Jeff-1.0 
WA6FWi 
http:foxsmercantile.com
Reply to
Fox's Mercantile

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