MDShunk

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Quote:
Originally Posted by Joe Momma
I was reminded above when reading about the dual switching, and remembered something about about every office space needs to have at least 2 switches(even if there are only 2 fixtures).

I haven't looked into the details quite yet, but was wondering what you guys know on this subject? -----------------

Joe, that particiular electrical requirement for dual switching is part of the International Energy Conservation Code, which has been adopted by most states now. I just got a copy of that code a few weeks ago, and the electrical requirements are pretty interesting. It's things we've been doing for years anyhow, but it's nice to read the real requirement in black and white. Here the one you're asking about:

805.2.2.1 Light reduction controls. Each area that is required to have a manual control shall also allow the occupant to reduce the connected lighting load in a reasonably uniform illumination pattern by at least 50 percent. Lighting reduction shall be achieved by one of the following or other approved method:
1. Controlling all lamps or luminaries;
2. Dual switching of alternate rows of luminaires, alternate luminaires or alternate lamps;
3. Switching the middle lamp luminaires independently of the outer lamps; or
4. Switching each luminaire or each lamp.
Exceptions:
1. Areas that have only one luminaire.
2. Areas that are controlled by an occupant-sensing device.
3. Corridors, storerooms, restrooms or public lobbies.
4. Guestrooms.
5. Spaces that use less than 0.6 Watts per square foot (6.5 W/m).

And here's another that's sorta interesting:

805.3 Tandem wiring. The following luminaires located within the same area shall be tandem wired:
1. Fluorescent luminaires equipped with one, three or odd numbered lamp configurations, that are recess-mounted within 10 feet (3048mm)center-to-center of each other.
2. Fluorescent luminaires equipped with one, three or any other odd-numbered lamp configuration, that are pendant- or surface-mounted within 1 foot (305 mm) edge-to-edge of each other.
Exceptions:
1. Where electronic high-frequency ballasts are used.
2. Luminaires on emergency circuits.
3. Luminaires with no available pair in the same area.
Here's a really nice power point that goes over most of the energy code electrical requirements:

http://www.energycodes.gov/training/...#523,20,Tandem Wiring

Pierre Belarge

Marc
your url does not work, so I am taking the liberty of rewriting it, I hope you do not mind. I think it is a great site, that is why I am doing this.

www.energycodes.gov/training

MDShunk

Thanks, Pierre !

Jim

What, exactly, is the definition of “Tandem Wiring”?

Jim

Maybe I answered my own question.

A pair of three or one lamp fixtures interconnected to utilize a two tube ballast?

Easy to wire, but a royal pain to troubleshoot, particularly in a location where it’s generally not done.