AC versus DC Power TOOL question

[OilyRascal]

I suspect I may have several DC powered tools (used with old Lincoln welders) among the pile of power tools in the shop and I'm wondering if there is some simple way to discern between an AC and a DC powered tool by looking at it.

Any help would be appreciated.

[Aunt Phil]

Given the age of what you're mining, it's a pretty safe bet they will be AC/DC universal.

Bear in mind the SA 200 only provides 1000 watts of DC which is pulled from the exciter of the machine in later models.  It's also rarely 120 volts, even with the machine turning @ 1800 rpm.

AC only tools came into being with SCR varispeed control.

Your "DC" tools should run well on AC.  Most tools are series connected motors.  A tool with a simple On/Off switch should run on either.

[rusty]

Screw in brush holders are also a pretty good indication it's a universal ac/dc motor, things that don't have them *may* work on dc, but may not, and if they don't they burn up ;P

plain light bulbs also work, as do any heating type things as long as they don't use too much power, and don't have electronic controlls, for example old soldering irons work just fine...

As Phil says, the power is limited, big angle grinders are often somewhat unhappy as are some 1/2 drills....

Also, just as an aside, many old universal motor tools are also metal cased tools, and you don't have a ground on a welding machine unless you provide one, so be extra carefull...

[OilyRascal]

Very helpful.  Thank you both!

[Aunt Phil]

Also, just as an aside, many old universal motor tools are also metal cased tools, and you don't have a ground on a welding machine unless you provide one, so be extra carefull...

Flowered hats are as close to being a posey as real weldors get Rusty, quit being all pansy about grounds.  Everybody knows the first man launched to the Moon was a pipe weldor and the launch device was a VanDorn Grinder.

Real weldors know on a SA machine you pull the trigger of the grinder for half a second to get it spinning and then you pull it again to get to work.  Sort of soft start before some salesman came up with that term.

[1930]

Real weldors know on a SA machine you pull the trigger of the grinder for half a second to get it spinning and then you pull it again to get to work.  Sort of soft start before some salesman came up with that term.

Actually they know to give it a spin with the fingers to get it started than push the trigger

[rusty]

>.soft start before some salesman came up with that term.

Years back, i worked in the engineering lab of a test quuiptment company.

Sales people would show up from time to time to try to sell us the latent and greatest (switching) power supplies. Most of them had 'Soft Start', most of them *depended* on having soft start to not self immolate.

We has a special test jig just for these fellows, we named it after the guy in the shop who built it, it was the 'Al' device. It consisted of a random interval timer, and a SCR type relay to turn things on and off.

Many many of those hopefull salesmen left with a box full of smoking debris.

We loved the Al device :)