DMX512 controlled LED light fixture project

This light will be used at the Oakland Scottish Rite auditorium. Currently the auditorium is illuminated by the column lights using HPL575 halogen light bulb that are 575W each. Each light produces 575W * 24lm/W1) = 13800lm each. There are 24 column lights producing total of 331200 lm. This is a minimum lighting which is not adequate for the auditorium size.

The power consumption of the lights is 575W * 24 = 13.8KW.

There are also the original lights mounted in a circle around the perimeter of the dome. There is x number of white 100W light bulbs, g number of green light bulbs and r number of red light bulbs. The number and light output is to be determined.

Design specifications

The goal is to replace the existing light bulbs and fixtures around the perimeter of the auditorium with LED light fixtures. The replacement should pay for itself in 5 years by saving electricity. The 5 year goal is to be able to finance the upgrade by 0% financing available from PG&E available for such projects.

  • The light output should produce xx lumens at the floor of the auditorium
  • Total power consumption should be « 50% of the current power consumption
  • The light should produce white spectrum with CRI better than 75
  • The light output should be controllable on granular level with individual control for red, green, blue and white
  • The ratio of output light intensity between white and RGB is to be determined
  • The control will be done by DMX, use DMX over Ethernet for the uplink from control station to the ceiling level
  • Input power is 110V
  • Design for reliability

Q: Should design for the new RDM protocol instead?


LED selection

  1. good performance/price → high ratio of lm/$


LED PN Datasheet Max op current Nominal lm2) Price@qty 100 100W eq3) price/100W eq
LRTBC9TP-CWD5-1+D5E7-25+A Data 250mA 62 3.41 25.80 88
MCE4CT-A2-0000-00A5AAAA14) Data 700mA 350 17.7 4.58 81.18
LTRBGFSF-ABCB-QKYO-Z Data 50 50 1.16 27.8 32
CLV1A-FKB-CJ1M1F1BB7R4S3 Data 25 22 0.52 72 37
GM5WA06260A Data 35 22.4 3.05 71 217
AAAF5060QBDZGSEES Data 30(50) 33 1.32 48 63
CREE XP-C 3x LED Data 350 40+65+27(132) 2.53+3.88+2.27(8.68) 12 105
XPCRED-L1-R250-00201 Data 350 40 2.53 12 105
XPCGRN-L1-R250-00801 Data 350 65 3.88 12 105
XPCBLU-L1-0000-00W01 Data 350 27 2.27 12 105

White LED

LED PN Data Max op current Nominal lm Max lm lm/W Price@volQty 100W eq5) price/100W eq Note
MLBAWT-A1-0000-000WE7 Data 175 18@80 25lm@120mA,3.5V 59 0.55 64 35 Used in Demo unit
MX6SWT-A1-0000-000CE7 Data 175 100@60 200lm@145@22.8(!) 60.4 1.38 7.5 10.0
STW8Q14BE-T0T5-GA Data 150 30.5@100 46lm@150@4.7V 64 0.266 36 9.57
XPEWHT-L1-0000-00BE7 Data 1000 94@350 225lm@1000@3.5V 64 2.13 7 15.14 Used by Esika
XBDAWT-00-0000-00000LBE7 Data 500 87@350 135 lm@500@3.0V 90 0.9 11.9 10.6 New from Cree

Power supply

The system will require reliable power supply source. Requrements:

  1. UL certified power supply
  2. Well known brand
  3. Sufficient power output ~400-500W
  4. Output voltage 48 -80V
  5. Fanless for relable operation

Medium 200-300W power supply option 1x PS for two lights

  • HRPG-300-36 300W, 36V with PFC and active surge current limiting

Small power supply option for each light


LED driver

Thermally clad PCB

Metal core PCB and standard FR-4 are commonly used circuit board materials in conjunction with Power LEDs. Bergquist’s Thermal Clad dielectric is a thin, thermally conductive layer bonded to an aluminum or copper substrate for heat dissipation. The key to Thermal Clad’s superior performance lies in its dielectric layer.This layer offers electrical isolation with high thermal conductivity and bonds the base metal and circuit foil together. Other manufacturers use standard prepreg as the dielectric layer, but prepreg doesn’t provide the high thermal conductivity and resulting thermal performance required to help assure the lowest possible operating temperatures and brightest light output for high-intensity LEDs.Thermal Clad circuit board materials are available from The Bergquist Company in four different thermal conductivities, High Power Lighting (HPL), High Temperature (HT), Low Modulus (LM) and Multi-Purpose (MP).



5-1-2011 Started Research

Links and other info

Light sources efficiency and efficacy

1 cd = 13 lm

TypeOverall luminous efficiencyOverall luminous efficacy (lm/W) Output lm Output cd
40 W tungsten incandescent1.9%12.6
60 W tungsten incandescent2.1%14.5 800 64
100 W tungsten incandescent2.6%17.5 1600 127
glass halogen2.3%16
quartz halogen3.5%24
high-temperature incandescent5.1%35
ideal black-body radiator at 4000K (or a class K star like Arcturus)7.0%47.5
ideal black-body radiator at 7000 K (or a class F star like Procyon)14%95
ideal monochromatic 555 nm (green) source100%683



DMX 512 specifications
  • DMX uses 256Kbit communication over RS485 bus. No error checking, no reliable delivery.
  • Addressing is manual, by switches or in software, no auto addressing.
  • DMX512 packe takes 1204 usec to 1 s.
  • Maximum is 32 devices per bus + master. There can be a splitter that will allow multiple chains of 32 devices connected to the master.
  • Max lenght is 1200m.
  • Nominal imepdance 120 Ohm, bus should be properly terminated.
XLR 5 pin connector
  1. Signal common
  2. Data 1- (Primary)
  3. Data 1+ (Primary)
  4. Data 2- (Optional)
  5. Data 2+ (Optional)

DMX Over Ethernet


efficacy for quartz halogen bulb
total summing all three colors
3) , 5)
number of LEDs required to replace one 100W incandescent light bulb 1600lm or 127cd
Four colors LED
dmx_led.txt · Last modified: 2015/04/16 16:26 (external edit)
CC Attribution-Noncommercial-Share Alike 4.0 International
Driven by DokuWiki Recent changes RSS feed Valid CSS Valid XHTML 1.0