So is a 240v Variac considered a tool as well?

Unfortunately Yes. Cant change the laws of physics.
I've used it on my die grinder to carve wood with HSS burrs, at full rpm they burn, at half speed they cut beautiful, and it still has lots of torque.
I added a bridge rectifier similar to the one in your photo to get pulsed DC. That operates a gear motor on a gearbox for a weld positioner. Mounted a 3 jaw chuck to hold pipe or hubs. Get the speed set then pull the trigger on the mig and get smooth consistent weld beads.
Lots of uses for them.

Greg
 
I have several used in different places. They work great for soldering irons to control the temperature. Also I use one on
my Croc-Pot as a warmer as the low control is still too hot. I have one in the shop to put in line with a battery charger.
That way you can give a battery a slow charge or a boost if the battery doesn't draw any current when trying to charge it.
Also I have used a Variac on a 4.5 inch angle grinder for less robust operations.


Edit: By the way, some Variacs control from zero volts up to line voltage only and others
control from zero to line voltage plus about 20 percent. Also be aware that some can
have more than one configuration. The markings on the terminal posts usually tell the
story.
 
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Variacs are very useful. I have two. Add an AC amp meter for repairing the old transistor power amps and power supplies. They are great for resistance type loads such as heaters, soldering irons, the old light bulbs, etc. Work pretty good for universal motors. Do not use on AC motors and fluorescent lights.
 
The 2.66 KVA that it says on yours is some respectable power, silverforgestudio. That is watts times volts divided by 1000.
 
OK- thank you all!

And I like the use on the grinder- understood about the torque- I am NOT anything electrical (heck- just started putzing about with machine tools a couple of years ago!) so I am definitely getting an education and direction to head- thank you ALL (even Monkey-shocker Mark!) HA!

Guys thanks- as I "gear up" and learn I am blessed to have several storage-boxes of stuff for free from older guys I helped clean things or shut down their shops- I know I am in the dark about some of this stuff- thanks for the compass points!
 
Another point: I believe that whole upper circular plate is electrically "live"- usually those units are enclosed and there's an insulated knob assembly that mounts on the top, so again, be careful if you do decide to use it.
Sorry I'm fresh out of monkeys today.
Mark S.
 
Understood Mark- I will be putting it back in the case it was in and getting a proper dial/face for when I get it back out- As I'm discovering exactly what these things are I'm making notes and putting them with the item so later I can remember/understand or know what part(s) I need to make these things work for me.

Think I'll break out the "barrel of monkeys" and glue them around the shop- and Ill shock one in your honor! HA!
 
silence dogood said:
Variacs are very useful. I have two. Add an AC amp meter for repairing the old transistor power amps and power supplies. They are great for resistance type loads such as heaters, soldering irons, the old light bulbs, etc. Work pretty good for universal motors. Do not use on AC motors and fluorescent lights.
Click to expand...

I use that exact model to control heaters in test equipment I've build. They work very well for resistive loads; I'd try not to use them too much for inductive loads, although they've been used to conduct high line/low line tests on some of our equipment.

They're built like a tank!
 
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Thanks Dulltool17- nice to know I have something that is in use (not from the 1950's like a lot of the things I got from this fellow)- and relatively well built!

Now I need to learn the difference in inductive versus resistance... back to the monkey-mix!
 
Quick rule of thumb - if the device (usefully) converts electricity to magnetism (and then to motion), it's inductive. The prime example would of course be a motor. If the device converts electricity into heat or (incandescent) light, it's resistive.

OK, exceptions/details:
1. You can use a Variac to run a transformer, which is basically an inductive "middle man" between the variac and something else. So look at the "something else."
2. Be aware that lights which use solid state circuitry (fluorescents, CFL, and many LED bulbs) are not resistive loads. The circuitry requires full voltage. LED bulbs that are labeled as dimmable might work with a variac.
3. As Silence Dogood pointed out, a "universal" motor is OK with a variac. Universal motors have brushes to get voltage directly to the windings of the rotor, so they'll work, but lose torque as well as speed. Motors without brushes depend on the field (fixed) windings inducing current in the rotor. Speed is mainly a function of frequency. If voltage is reduced, the motor will still try to run at the same speed, but at severely reduced output power, and may well overheat.
4. Solid state devices contain internal voltage regulators, so that the circuit elements can be fed the correct power levels. Reducing the input voltage will have almost no effect at first. Then when it drops below the level the voltage regulator can handle, the device will precipitously stop working.

Hope this helps.
 
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