what does "dimmable" mean in the led world?

Organized by:

What does “Dimmable” mean in the LED world?

Organized by:

As Presented By: Eric Lind, Lutron

LEDucation 5 March 16th 2011 Media Sponsor:LEDucation 5   – March 16th, 2011New York, NY

Media Sponsor:

WWW.LEDUCATION.ORG

What does “dimmable” mean in the LED world?

Eric Lind Lutron Electronics Co., Inc

Chapters

1 Dictionary Terms2 Expectations3 LED Technology and Control Options4 Technical Concerns5 The Energy Story and Next Steps

1 Dictionary Terms

Orientate

Conversate

Dimmable

Redolent ‘suggestive;’ at best, that is what dimmable infers

1 Dictionary Terms

None of us recommend lamps that are‘bright’

None of us recommend fixtures that provide ‘more than a few lumens’

We cannot afford to use the equally wishy-washy term that no one understands of

‘dimmable’

‘Dictionary’ Terms

Missing: 1. Dimming Performance 2. Rated Life

Proposed LED Labeling System(SSL Quality Advocates)

Incandescent lamp performance:• Color temperature• CRI > 90• Light output controlled easily through

voltage reduction

Incandescent dimming performance:• Smooth and continuous to < 0.1%• No flicker or shimmer• No pop-on• No drop-out• No dead travel• Use of standard controls: $3 - 200

2 Customer Expectations

6

Dimming Expectations

• We can dim – And have been for 80+ years (autotransformers)

• We should dim, independent of source– energy savings and efficiency (ASHRAE 90.1 – 2010)– space flexibility; ability to change the light level based on the

activity– ambiance; dining vs cleanup– productivity; different light levels for different people (age,

preference)– safety and comfort; is it better to enter a dark space or a space at

5%?– extended system life

Dimming Expectations

Control Factors: ASHRAE 90.1-2010 draft

• Manual, continuous dimming control or programmable multi-level dimming control 0.05

• Programmable multi-level dimming control using programmable time scheduling 0.05

• Multi-level occupancy sensors 0.05

• Automatic continuous daylight dimming 0.20

9

Measured vs perceived light:

• Measured light: the amount of light as shown on a light meter

• Perceived light: the amount of light that your eye interprets due to dilation

• 20% measured = 45% perceived

Dimming Expectations

10

In order for LEDs to take the place of existing light sources,

they need to be controllable – with details.

The Challenge (and the opportunity)

11

3 LED Technology and Control Options

LED Fixture:

LED Lamp:

Line voltage control:• Forward Phase control

– Incandescent and magnetic low voltage (MLV) dimmers

• Reverse Phase control– Electronic low voltage (ELV) dimmers

• 3-wire control– Fluorescent (F) dimmers

• Power-line carrier

Low voltage control:• 0-10V• Digital (DALI, EcoSystem®)• DMX-512• DC

LED Control Options

12

Forward Phase

Pro: Largest installed base

Con: Hit or miss performance with LEDs

Reverse Phase

Pro: Typically performs better than forward phase

Con: More expensive than forward phase and requires neutral wire

LED Control – Phase control

13

14

0-10V

Standard: IEC 60929 Annex E-1

Pro: Industry standard control type

Con: Poor performance with line noise and long wire runs

LED Control: Low voltage analog

15

DALI

Standard: IEC 62386-101, -102, -201, -202, ...

Pro: Individual addressing of fixtures and flexible control wiring

Con: System startup and programming required, slow response time if sequences or color changing is required

LED Control: Low voltage digital

16

DMX-512

Standard: USITT 512-A

Pro: Color mixing and varying color intensity, fast time response

Con: More complex wiring and integration for general illumination

LED Control: Low voltage digital

LED Control - Performance Questions

• What is the dimming range?

• Does this performance include any of the following:• Flicker• Pop-on• Drop-out• Audible noise (not EMI)• Dead travel• Long start times (>2 seconds)

• Will you see color shift?

• What is the THD for the lamp or fixture?

• What is the rated life?

• Current inrush spikes can cause the LED lamp to appear like a much higher wattage product to the dimmer

• Applying too many LED loads to a dimmer may cause the dimmer to fail prematurely or trip the circuit breaker, even if the dimmer or circuit rating has not been exceeded!

• Maximum number cannot be determined by “dimmer’s capacity and the fixture’s rated wattage”

• Ask your controls manufacturer.

4 Technical Concerns

Inrush Current (@ turn on)

Inrush Current – INC vs LED

Technical Issues Still Being Evaluated

• Electromagnetic Interference (EMI) or Radio Frequency Interference (RFI)– For fixtures with dedicated drivers and LED

modules, pulse width modulation vsconstant current reduction

• Arc-Fault Breakers tripping (independent of previously mentioned overload condition)

5 The Energy Story and Next Steps

22

“We will not need to dim LED lighting because we will be saving so much energy.”

- Anonymous

“The success of our industry has created a behavioral script that we expect the downlights overhead to dim.”

- Mark Lien (paraphrase ofAugust 2010 LD+A article)

“The test of a first-rate intelligence is the ability to hold two opposed ideas in mind at the same time and still retain the ability to function.”

- F. Scott Fitzgerald

The Energy Story

23

Power Usage vs. Measured Light for Lutron LED drivers

0%

20%

40%

60%

80%

100%

0% 20% 40% 60% 80% 100%

Measured Light

Pow

er

Power Usage vs Measured Light for an LED Fixture (example shown is a fixture with a dedicated LED Driver)

Standards emerging:• NEMA dimming white paper (standard in process)

http://www.nema.org/stds/lsd49.cfm

What to do now:• Mock-up, mock-up, and mock-up• Use products from companies that you trust • Consult published control compatibility information• Ask LED product manufacturers the following

questions before purchasing their product (next slide)

24

Next steps

LED product manufacturer checklist: 1. What is the dimming range of the product?2. What type of dimmer does the product operate on?

• Forward phase control• Reverse phase control• 0-10V• DALI• DMX-512

3. Is the dimming range smooth and continuous? Is the light level stable at every dimmed level or are there points of flicker? Is the color consistent throughout the dimming range? Is the performance consistent with one lamp/fixture per dimmer and two or more fixtures per dimmer?

4. What is the minimum and maximum number of fixtures/lamps that can be used on a dimmer or control system?

5. Have they tested multiple dimmers/control system of the same type from multiple manufacturers?

Next steps

Questions?

26

Thank you

Eric LindLutron Electronics Co., Inc

fjlind@lutron.com