The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!


2017 NEC and Related
2017 NEC
Now Available!

Recent Posts
Industrail Control Panel bonding per 409.108
by sparkyinak
Today at 03:17 PM
Calling all Non-US members!! (Non-US only)
by aussie240
Yesterday at 02:39 AM
Photo Upload Tutorial
by DanK
12/06/16 11:35 PM
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
On Delay Relay with Auto Reset
by Potseal
12/01/16 09:59 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 13
HotLine1 9
sparkyinak 8
Texas_Ranger 8
Trumpy 6
Who's Online
0 registered (), 248 Guests and 6 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 3 1 2 3 >
Topic Options
Rate This Topic
#153948 - 01/04/04 09:03 PM Dual level switching
Ryan_J Offline

Registered: 08/19/03
Posts: 1355
Loc: West Jordan, Utah, USA
In another thread, the topic turned to energy conservation, which makes me wonder: In your state/county/city/neck o' the woods, is dual level switching a requirement in commercial buildings?
Ryan Jackson,
Salt Lake City

Building Codes & Related References
#153949 - 01/05/04 12:06 AM Re: Dual level switching
Trumpy Offline


Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Hate to look like a silly person, but could you please define the term "Dual level switching?.
Let's face it, these days if you're not young, you're old - Red Green grin

#153950 - 01/05/04 04:38 AM Re: Dual level switching
PCBelarge Offline

Registered: 06/08/03
Posts: 657
Loc: Dobbs Ferry, NY, USA
The energy conservation construction code has many rules for conserving energy. One of the rules requires buildings of 5,000 sq ft and larger with rooms that are 250 sq ft to have two means of controlling the lighting. One means is manual (switch), the other either part of a system or a means of automatically turning the lights off. This can all be in one unit, such as an Intermatic timer with manual override.

In lower NY, it is not being enforced, but on larger jobs the engineers are specifying it.

Pierre Belarge

#153951 - 01/05/04 05:22 AM Re: Dual level switching
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
Ryan I have no idea of the code requirements.

I do know that as Pierre stated the engineers are including this in the drawings.

Almost as many ways to accomplish this as there are engineers.

In open office spaces we often put in light level meters that will take out half the lighting when the windows provide enough light, along with motion sensors that kill the lights entirely when unoccupied.

In small private offices most times we have "a, b, switching" Switch "a" runs the center tubes of the fixture and switch "b" the outside tubes, this is also overridden with an occupancy sensor.

Where we have hi or low bay HIDs we may again have a light level sensor that puts the HIDs in some sort of low output mode, this takes a third wire to each fixture.

I have never had an inspector ask any questions on any of this.
Bob Badger
Construction & Maintenance Electrician

#153952 - 01/05/04 07:33 AM Re: Dual level switching
Ryan_J Offline

Registered: 08/19/03
Posts: 1355
Loc: West Jordan, Utah, USA
Mike dual level switching is what Bob (Iwire) is describing. Basically, two switches control each light.

The IECC states that in commercial buildings there must be a means provided to decrease lighting by 50% in (almost) every room. I call this out on plan review quite often.

Bob: I hope you continue to not hear it from inspectors. If it got through the plan review stage without being caught, it is way too late to bring it up.
Ryan Jackson,
Salt Lake City

#153953 - 01/05/04 01:18 PM Re: Dual level switching
Roger Offline

Registered: 05/18/02
Posts: 1779
Loc: N.C.
In NC, state funded or controlled projects such as schools, we must provide 50% / 50% or as Iwire says a b switching.

There are also occupancy sensors on some of the A/C equipment.

The Federal jobs we have done in the last few years are pretty much as Pierre describes.


#153954 - 01/05/04 05:02 PM Re: Dual level switching
Nick Offline

Registered: 08/13/01
Posts: 603
Loc: Riverside, CA
In California this is covered under Title 24 regulations.
Something of interest-
I have done allot of theme park work and they are exempt from these rules.

#153955 - 01/06/04 01:22 AM Re: Dual level switching
Scott35 Offline

Broom Pusher and

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
Adding to Nick's reply in regards to Title 24 - Part 6 (California's State Building + M/E/P Codes are Title 24 - Part "_X_"):

California Energy Commission's Standards for Energy Conservation in New, Altered or Remodeled, & Additions in Residential and Non-Residential Occupancies cover the Building's Envelope (Framing, Insulation, Windows, etc.), M/E/P, and Appliances.
Anyone who has worked in the Construction Fields out here has at least heard of these Standards - and will be referred to in "Trade Slang" as "TITLE 24".

"a/b" Switching began in late 1970's for Commercial Installations.

By mid 1980's, Commercial Lighting included "Slave/Master" fixtures, Zones of upto 5,000 Sq. Ft. separately controlled via auto shutoffs (if all under one meter), multi level lighting controls ("a/b - c/d - e/f"), and use of energy saving Ballasts + Lamps (F40T12 Lamps rated for 34 Watts).

By mid 1990's, Daylit areas became included into "Dimming Scheme", lower TLP (Total Lighting Power) per Occupant Category, and more of an emphasis placed on automatic occupancy sensors for credits.
Also, 1 Family Residential installations became included into Standards (for Lighting, that is; - Mechanical and Building Envelope already involved since first adoption in 1970's).

Things took a gigantic change after the rolling blackouts situation.
The Compliance Standards at that time were the 1998 version. This version was quite different than the previous version of 1995 - but not as drammatic of change between 1998 and the currently used version - 2001 Nonresidential Compliance Manual.

The rolling blackouts modeled a Worse-Case-Scenario for the Energy Commission, and with this in mind - figured to revise many currently enacted Standards - both in the Residential and the Non-Residential Standards.

For more information regarding these Compliance Standards, check out:

CEC-Title 24 Homepage

These energy conservation items are compiled into all Architectural & M/E/P/ Plansets.
Also per Business codes, if the Contractor is also doing the Installation, that Contractor may perform the designing and take responsibility upon the Documents as both designer and author (such as Design / Build).

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

#153956 - 01/06/04 03:09 AM Re: Dual level switching
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
I can't help thinking that in many places these days we're simply installing too many lights in the first place.

Some years ago I checked out the lighting in a small supermarket which had just been built near to where I lived. It had a small entrance lobby, about 20 feet square, with full-height windows on two sides. That lobby alone had something like 3kW of lighting in it.

We simply don't need supermarkets illuminated to the level of an operating theater!

#153957 - 01/06/04 04:53 AM Re: Dual level switching
Roger Offline

Registered: 05/18/02
Posts: 1779
Loc: N.C.
Paul, I have thought the same thing. We have an engineering firm in this area who would install a fixture in every opening of a grid ceiling if they could.

Don't get me wrong, I think the world of this group, but they have a "overkill" attitude on lighting.


[This message has been edited by Roger (edited 01-06-2004).]

Page 1 of 3 1 2 3 >

ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals