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### lights schedule and dimming interaction

I have difficulty understanding from the E+ manual how the lights dimming and lights schedule interact. For example, let’s assume that I have an illumination target of 500lux, my lighting level is 200 W, and my lights schedule is "from 12am to 7am, 0.2; from 7am to 5pm, 0.9; and from 5pm to 12am, 0.5;”. Case 1: At 11AM I have 600lux from daylight then the Artificial lights (AL) are off. Hence, they would require 0(i.e., lights off) x 0.9 (schedule) x 200W (lighting level) = 0.
Case 2: At 11AM I have 400lux from daylight then the Artificial lights (AL) are on. Hence, they would require X(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18X. Case 3: At 11AM I have 50lux from daylight then the Artificial lights (AL) are on. Hence, they would require Y(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18Y > 18X. Where X, Y are selected by the dimming algorithm (E+ just says “For Lighting Control Type = 1 (continuous), the lowest power the lighting system can dim down to, expressed as a fraction of maximum input power (see figure, below). Fig. 54.” I want to confirm that when daylight is below the illumination target, artificial lights kick in at a complimentary level to achieve the 500 lux target. ASHRAE sets the schedule at 0.9 x 200W. Will I still get my 500lux or not. I am asking because E+ says “This is the lighting level that would be produced at this reference point at night if the overhead electric lighting were operating at full input power.” Full input power is 200W and not 0.9x200W as the ASHRAE schedule recommends putting in.

 2 No.2 Revision Julien Marrec 26528 ●37 ●69 http://www.effibem.com/

### lights schedule and dimming interaction

I have difficulty understanding from the E+ manual how the lights dimming and lights schedule interact. interact.

For example, let’s assume that I have an have:

• illumination target of 500lux, my 500lux
• lighting level is of 200 W, and my lights W
• ights schedule is "from 12am to 7am, 0.2; from 7am to 5pm, 0.9; and from 5pm to 12am, 0.5;”. 0.5;”.

### Case 1: 1

At 11AM I have 600lux from daylight then the Artificial lights (AL) are off. off.

Hence, they would require 0(i.e., lights off) x 0.9 (schedule) x 200W (lighting level) = 0.

### Case 2: 2

At 11AM I have 400lux from daylight then the Artificial lights (AL) are on. on.

Hence, they would require X(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18X. 18X.

### Case 3: 3

At 11AM I have 50lux from daylight then the Artificial lights (AL) are on. on.

Hence, they would require Y(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18Y > 18X. Where X, Y are selected by the dimming algorithm (E+ algorithm

E+ just says “For says:

For Lighting Control Type = 1 (continuous), the lowest power the lighting system can dim down to, expressed as a fraction of maximum input power (see figure, below). Fig. 54.” 54.

I want to confirm that when daylight is below the illumination target, artificial lights kick in at a complimentary level to achieve the 500 lux target. ASHRAE sets the schedule at 0.9 x 200W. Will I still get my 500lux or not. not?

I am asking because E+ says “This says:

This is the lighting level that would be produced at this reference point at night if the overhead electric lighting were operating at full input power.” power.

Full input power is 200W and not 0.9x200W as the ASHRAE schedule recommends putting in.

 3 retagged __AmirRoth__ 4388 ●5 ●16 http://bleedinggreenna...

### lights schedule and dimming interaction

I have difficulty understanding from the E+ manual how the lights dimming and lights schedule interact.

For example, let’s assume that I have:

• illumination target of 500lux
• lighting level of 200 W
• ights schedule is "from 12am to 7am, 0.2; from 7am to 5pm, 0.9; and from 5pm to 12am, 0.5;”.

### Case 1

At 11AM I have 600lux from daylight then the Artificial lights (AL) are off.

Hence, they would require 0(i.e., lights off) x 0.9 (schedule) x 200W (lighting level) = 0.

### Case 2

At 11AM I have 400lux from daylight then the Artificial lights (AL) are on.

Hence, they would require X(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18X.

### Case 3

At 11AM I have 50lux from daylight then the Artificial lights (AL) are on.

Hence, they would require Y(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18Y > 18X. Where X, Y are selected by the dimming algorithm

E+ just says:

For Lighting Control Type = 1 (continuous), the lowest power the lighting system can dim down to, expressed as a fraction of maximum input power (see figure, below). Fig. 54.

I want to confirm that when daylight is below the illumination target, artificial lights kick in at a complimentary level to achieve the 500 lux target. ASHRAE sets the schedule at 0.9 x 200W. Will I still get my 500lux or not?

I am asking because E+ says:

This is the lighting level that would be produced at this reference point at night if the overhead electric lighting were operating at full input power.

Full input power is 200W and not 0.9x200W as the ASHRAE schedule recommends putting in.

 4 retagged __AmirRoth__ 4388 ●5 ●16 http://bleedinggreenna...

### lights schedule and dimming interaction

I have difficulty understanding from the E+ manual how the lights dimming and lights schedule interact.

For example, let’s assume that I have:

• illumination target of 500lux
• lighting level of 200 W
• ights schedule is "from 12am to 7am, 0.2; from 7am to 5pm, 0.9; and from 5pm to 12am, 0.5;”.

### Case 1

At 11AM I have 600lux from daylight then the Artificial lights (AL) are off.

Hence, they would require 0(i.e., lights off) x 0.9 (schedule) x 200W (lighting level) = 0.

### Case 2

At 11AM I have 400lux from daylight then the Artificial lights (AL) are on.

Hence, they would require X(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18X.

### Case 3

At 11AM I have 50lux from daylight then the Artificial lights (AL) are on.

Hence, they would require Y(i.e., lights on) x 0.9 (schedule) x 200W (lighting level) = 18Y > 18X. Where X, Y are selected by the dimming algorithm

E+ just says:

For Lighting Control Type = 1 (continuous), the lowest power the lighting system can dim down to, expressed as a fraction of maximum input power (see figure, below). Fig. 54.

I want to confirm that when daylight is below the illumination target, artificial lights kick in at a complimentary level to achieve the 500 lux target. ASHRAE sets the schedule at 0.9 x 200W. Will I still get my 500lux or not?

I am asking because E+ says:

This is the lighting level that would be produced at this reference point at night if the overhead electric lighting were operating at full input power.

Full input power is 200W and not 0.9x200W as the ASHRAE schedule recommends putting in.