https://stream.echo6.co/videos/watch/5c6e7301-f8ec-47a4-bfb3-277b821fc26a A variac is basically a variable auto-transformer that allows you to adjust the voltage between zero and the local mains supply voltage, or more if tapped mid-winding. They find use in specialist applications where it's useful to ramp the mains voltage up slowly for regulation or testing. Some applications would be inverter, motor drive repair, soft start of vintage electronics and some specialist lighting applications where lights need to be dimmed without phase angle noise. These units do not provide isolation from the mains supply, as they are just a single winding with an adjustable tap. I've sometimes wondered how they can seamlessly jump from one winding to another without bridging loops and crating shorted transformer turns. Since I had my unit open for fitting a new digital meter, I thought I'd test that with a thermal imaging camera. If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- http://www.bigclive.com/coffee.htm This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty. Mon, 13 Apr 2026 20:42:58 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://stream.echo6.co https://stream.echo6.co/client/assets/images/icons/icon-512x512.png https://stream.echo6.co/videos/watch/5c6e7301-f8ec-47a4-bfb3-277b821fc26a All rights reserved, unless otherwise specified in the terms specified at https://stream.echo6.co/about and potential licenses granted by each content's rightholder.