What is this “Variac” Thing?

A Variac (also known as an Autotransformer) is a variable transformer, which allows the user a convenient way to control the power to an AC appliance.  In our context, it’s typically used to adjust the output of a heating device. The variac currently at the Makery is a 20-amp model manufactured by PowerStat.  We’ve configured it to scale voltage only in the down direction, so that the output range is 0-110vac (or whatever line voltage happens to be).  The transformer is outfitted with standard AC outlet fittings, and is mounted to a board for easy transport.  It should be noted that this transformer is NOT isolated, so the output could still be hazardous, regardless of how low the voltage happens to be set.  As with most other equipment, the variac is stored in the TOOLS cabinet.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>