Breakers are designed to trip anytime the circuit draws a current above the rating for a period of time. The time the breaker takes to trip is a function of how high the circuit amperage is compared to the breaker rating. The higher the amperage above the rating, the faster the breaker will trip. Breakers […]

I don't do much in the way of “rack” refrigeration. However, I recently had a conversation with experienced rack refrigeration tech Jeremy Smith, and he got me thinking about EPR valves. I've heard EPR (evaporator pressure regulator) valves called suction regulators or hold back valves. In essence, they hold back against the suction line to […]

Suppose you have two extension cords. One is a nice, thick #10 50′ cord with good ends, and the other is a crappy #14 25′ cord. Unfortunately, you need to connect them both to get to your drill 75′ away. Which do you connect to the plug, and which to the drill? Come up with […]