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geekhack Community => Other Geeky Stuff => Topic started by: nowsharing on Sat, 20 August 2011, 23:26:27

Title: Uses for a variac?
Post by: nowsharing on Sat, 20 August 2011, 23:26:27

hi geekhack!

I picked up an old variac (10A Powerstat) in barely used condition at a sale. Could I use this with a Champion juice machine? What other good uses are there for it?

I'm probably not the kind of person who should own one of these, but I thought "hey $5 variac, OK."

Title: Uses for a variac?
Post by: nowsharing on Sun, 21 August 2011, 00:02:17

Hmm, the juice machine is rated at 5.4A, so I'm not sure how that affects things.

Title: Uses for a variac?
Post by: The Solutor on Sun, 21 August 2011, 06:25:27

They were used mainly in TV repair laboratories, useful to repair traditional TV.

The still make senses in laboratories as 1/1 transformers to have the 110 or 220 lines disconnected from the ground, for security reasons (this way you can touch one of the two wires w/o any risk of electric shock).

Title: Uses for a variac?
Post by: kps on Sun, 21 August 2011, 09:31:45

They are useful in bringing up any old electronic equipment, where electrolytic capacitors have aged.

Title: Uses for a variac?
Post by: nowsharing on Mon, 22 August 2011, 12:52:48

So nothing useful juice machine-wise? I read that people are using them to give stable power to their coffee roasters, which is something that I own (a Behmor), but I don't think that my line voltage fluctuates much.  

I have a 60s Traynor amp that I will one day want to plug back in, maybe I'll just put it away until then.

Title: Uses for a variac?
Post by: Konrad on Thu, 25 August 2011, 03:30:03

I still use one to test PSUs. See what happens on the meter when simulating a PC load (or in fact actually using it to run a loaded up junky old PC) and the voltage is varied. The manufacturer bragsheet is always fulla **** (or at least one needs to assume such is the case in a modern world filled with Shenzhen electronics), actual test bench data never lies or omits info of real importance. If I'm gonna upgrade a cluster or even spend some big bucks on a high end PSU for personal use I wanna ensure I get something worthy. My computers don't suffer brain damage from momentary voltage dips, drops, brownouts, surges, and spikes. Then again, I only use the autotransformer about twice per year, most of the time it's just a handy flat surface for holding screws and heatsinks.