Multilevel lighting control

In my personal opinion, the strategy you describe would meet the requirements of 4.1 Interior Lighting #3 Lighting Control. If you look at the 4.0 version of the credit, it talks about: "at least three lighting levels or scenes (on, off, midlevel)." Your strategy allows the creation of "scenes" by switching on and off different groups of lights, and will certainly give you "on, off, midlevel" in the room.

But why don't you provide dimming of each group of lights instead of only on/off switching? Dimming of LED fixtures is easy and inexpensive.

was this approved for the submission ?

Hello Michael, Glenn,  I think that configuration dosen't comply with LEED requirements. I always undrestood that multilevel control must be activated on each fixtures (DIMMABLE fixtures). Each fixture must allow reduce its maximum brightness to the multilevel (between 30% to 70% of power). Reduction strategy for operating a part of a circuit (20% or 50% or 70% of lighting numbers) dont must be acceptable.  Can someone tell me if i'am wrong? 

Couple things on this discussion - the change mentioned in v4.1 for open office spaces still requires a "zone" of light directly over workstations to be multilevel and controlled in the room Multi-level means specifically on off plus something in between (30-70% range). It removed the requiement for each workstation/desk to have local task lighting but the room must be zoned to allow for occupants to change the levels where they work. This is not a whole room situation so varying the light in another part of the room does not give anyone control over their own work area. Additionally, there is no requirement for each fixture to be controlled individually - that may ot be what was suggested above, but it is not the case. Think of the intent of the credit - allow local control over what light hits an individual's workspace and it will keep you in line with the requirements.

Quick follow up - since all LEDs are dimmable I wonder why there would even be an on/off switch? The only cost savings is the type of switch or am I maybe missing some piece of the proposed design?