1. Illumination Devices
Measurement Unit

2. Measurement Units Cd (Candela):
Lumen (lm): amount of light comes out from source
Lux (lx): amount of light reflect on a surface (1 lx = 1 lm per square meter)

3. Lux (lx) Illuminance Flux density: flux per area
Measurement tool: lux-meter

4. Lux (lx) กรณีกฎหมายมีความขัดแย้งกัน ให้ยึดถือกฎหมายที่มีศักย์สูง กว่า
ถ้าไม่มั่นใจยึดถือค่าไม่น้อยกว่า กฎหมายทุกฉบับ
วารสาร TIEA Newletter ของสมาคมไฟฟ้าแสงสว่างแห่งประเทศไทย (ปีที่ 1 ฉบับที่ 2)

5. Illumination Devices
Lamp Technology

6. Lamp Technology
Incandescent lamp: produces the output light by heating the filament.
Gas discharge lamp: produces the output light by electrically forcing an electron in the gas atom to change its current level.
Semiconductor lamp: produces the output light by moving an electron between P-N junction.

7. Gas-discharge Lamp Technology
Low pressure:
Fluorescent lamp: asldfdsaf
Fluorescent line sources
Fluorescent point sources
CDM: produce
HID: asldfdsaf
LED:

8. Technology Considerations
Lamp Cost
Initial Cost (Cost per lamp)
Cost per life-time
Efficacy
Maximum Available Lumen
Light Distribution Profile
Start-up Time
Dimming Capable

9. Technology Considerations
Color Temperature
Color Representation
Life Time
Lamp Lumen Depreciation (LLD)

10. Ratio of light output to its active power (lm/W)
Efficacy
Ratio of light output to its active power (lm/W)
Technology
(lm/W)
100 W tungsten incandescent
13.8
9–26 W compact fluorescent
46-72
T12 tube with magnetic ballast 60
T8 tube with electronic ballast
80-100
T5 tube
70-100
white LED
10-150
metal halide lamp
65-115
low pressure sodium lamp

11. Color Temperature Light Color Reference to the blackbody radiator

12. Color Temperature

13. Correlated Color Temperature (CCT)
“color matching” a light source to the blackbody radiator scale
Metameric Light Sources: different spectral distributions but with the same CCT

14. CRI: Color Rendering Index
Effect of light to the color of objects
Comparing at the same CCT

15. Light Distribution Profile
Linear
point-small beam
point-large beam
Compensate by cover

16. Lighting Technology Comparison
CRI
(~)
Efficacy
(lm/W)
Lifetime
(x1,000 hours)
Lumen Maintenance
Color Temp.
(K)
Power
(W)
Incandescent
100
10-19
10%-20%
2,500-3,000
15-250
Halogen
11-19
2-6
< 10%
2,850-3,050
CFL
(Compact Fluorescent Lamp) 83
60-70
9-12
10%-30%
2,700-5,000
5-55
Fluorescent
(Linear Fluorescent Lamp) 80
80-100 20
2,700-6,500
Mercury Vapor 50
25-50
> 24
25%-40%
3,300-3,900
40-1,000
Metal Halide 68
46-100
5-10
30%
3,000-4,400
32-1,500
HPS
(High Pressure Sodium) 22
20%
1,900-2,100
35-1,000
White LED
65-90
20-50
CRC handbook of energy efficiency by Frank Kreith, Ronald Emmett West
LIGHTING TECHNOLOGIES: A GUIDE TO ENERGY-EFFICIENT ILLUMINATION by Energy Star

17. Fluorescent Lamp
T5 v.s. T8

18. Fluorescent Dimension
Tn: n represents the diameter of the tube.
T5: 5/8 in
T8: 8/8 in
T12: 12/8 in
Norminal
Length
Actual T5
T8 or T12
2 ft
21.6 in
23.3 in
3 ft
33.4 in
35.2 in
4 ft
45.2 in
47.2 in

19. Comparison on Operating Tmperature
Optimal temperature: 35 oC for T5 and 25 oC for T8 or T12

20. Comparison on Lamp Efficacy
T5 has better “Lamp Efficacy” than T8, but the “System Efficacy” seems to be slightly better !!

21. Comparison on Life Time
T5 has longer life time than T8 (T12=CW/HO)
T5 has better lumen maintemance than T8

22. T5 v.s. T8 in the market T5 is more expensive, due to new technology.
The price is going down.
T5 is more difficult to find.
More T5 produce are on the market.
Compatibility with the existing systems.
Adapter for T5 in T8 socket is available.

23. Backup

24. T5 Fluorescent System

25. T8 Fluorescent System