Educators love lockout relays, and we also love pretending you will still see them out in the field all the time. Sometimes, I have to look myself in the mirror in the morning and sadly repeat, “Lockout relays are dead.” I have to say it several times before the reality sinks in. Before I get […]

Connecting more than one wire on or under a single lug or connection point is called “double lugging,” and it is ONLY allowed in line voltage wiring under one condition, according to NEC 110.14: If the terminal, lug, or connector is specifically rated for more than one wire In the case of a conductor splice, […]

The HVAC industry uses all sorts of fancy words to classify refrigerant. As such, there are all sorts of complicated refrigerant acronyms: HFC, HCFC, CFC. Let's also not forget the mythical zeotropic, azeotropic, and near-azeotropic descriptors. Let's simplify those. (Though if you want to go back to the basics first, check out this article on […]