If a lighting ballast fails, do you change it out hot? That's a fairly common practice, but you can get electrocuted by 277V just as surely as from a higher voltage. If you're on a ladder, the fall ...

The special provisions for electric-discharge lighting systems of 1,000V or less can be found in Part XII of Art. 410. As noted in 410.130(E), "The ballast of a fluorescent luminaire installed indoors ...

In this section you'll find photographic features that explore holidays and photography courses, details about members meetings, trials and tribulations of installing new software along with general ...