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The National Electrical Manufacturers Association (NEMA) has released three new white papers on lighting.

They cover the following topics:

Fluorescent lamp and electronic ballast compatibility in applications where there is frequent switching;
Designations for HID lamps; and,
Recommendations for appropriate HID lampholders to minimize potential base arcing with certain HID wattage lamps.
To download these free white papers, click on the links below. You must have Adobe Acrobat Reader installed in order to read these PDF-formatted files.

Compatibility of Fluorescent Lamps and Electronic Ballasts in Frequently Switched Applications gives some guidance in the selection of ballast type as a function of lamp switching rate to achieve the desired energy savings while maintaining acceptable lamp life.

Marking of Luminaire Codes on Metal Halide Lamps, discusses designations for HID lamps specified in ANSI standard C78.380.

NEMA Lamp Section Recommendation: Use of Appropriate HID Lampholders to Minimize Potential Base Arcing with Certain HID Wattage Lamps, reports on findings of a task force consisting of members of NEMA Lamp and Luminaire sections investigating reported cases of arcing between an HID lamp base and the lampholder in some field installations.