Why is it called single-phase 240 when there are two opposing phases (or legs)? I wondered why we called two 120v opposing legs “single-phase 240” for years. Then someone pointed out to me that a typical “single-phase” pole transformer only has one power leg entering and two coming out. That freaked me out. How can […]

This tip will be like an episode of Columbo; we will start with the what and who and then get to the why. Don't pump down a scroll into a vacuum. Don't run a scroll in a vacuum. Don't run a high voltage megohmmeter or Hi-pot test on a scroll (As a general rule, don't […]

I remember it like it was yesterday. It was my first day of work as a trainee at my first technician job, just a wet-behind-the-ears kid fresh out of trade school. It was a Monday morning, and the technicians and I were standing in the dusty warehouse surrounded by stacks and stacks of brand new […]