CC and CV driver selection

LIGMAN TRAINING CONSTANT CURRENT AND CONSTANT VOLTAGE DRIVERS

1

SHOULD I USE CC OR CV? • Wherever possible, use Constant Current drivers • LEDs are designed for constant current circuits, and the CC ensures a strong stable lumen output • Constant Voltage SELV drivers ensure that the supplied Voltage does not exceed safety levels following IEC60364-7-702 • Constant Voltage circuits need current limiting resistors to prevent thermal runaway.

Without a current limiting resistors the LED have a lower life time.

• When calculating the driver size and power, care must be taken for Voltage drop (see following slides)

WHICH LUMINAIRES ARE CV COMPATIBLE? • The following luminaires contain current control diodes, which mean they can be used with 24V DC Constant Voltage drivers:

2

OREGON 1

LBX 2 & 4

NEVADA

LADOR 1

UTAH 1 & 2

PATCHI 1 & 2

ALDO

IF THE CUSTOMER WANTS TO USE LESS DRIVERS? • The following luminaires can be used with Constant Voltage drivers: PRODUCT ID

PRODUCT SERIES

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

OR-60894

OREGON 1

1.5

3

4.5

6

7.5

9

10.5

12

13.5

15

16.5

18

19.5

21

22.5

24

25.5

27

28.5

30

OR-60895

OREGON 1

1.5

3

4.5

6

7.5

9

10.5

12

13.5

15

16.5

18

19.5

21

22.5

24

25.5

27

28.5

30

ALD-30001

ALDO 1

6

12

18

24

30

36

42

48

54

60

66

72

78

84

90

96

102

108

114

120

ALD-30011

ALDO 1

12

24

36

48

60

72

84

96

108

120

132

144

156

168

180

192

204

216

228

240

ALD-30121

ALDO 2

18

36

54

72

90

108

126

144

162

180

198

216

234

252

ALD-30111

ALDO 2

24

48

72

96

120

144

168

192

216

240

ALD-30131

ALDO 2

36

72

108

144

180

216

252

ALD-30171

ALDO 3

48

96

144

192

240

LB-40437

LBX

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

32

34

36

38

40

LD-50002

LADOR 1

6

12

18

24

30

36

42

48

54

60

66

72

78

84

90

96

102

108

114

120

LD-50012

LADOR 2

13

26

39

52

65

78

91

104

117

130

143

156

169

182

195

208

221

234

247

260

LD-50022

LADOR 3

18

36

54

72

90

108

126

144

162

180

198

216

234

252

LD-50032

LADOR 4

36

72

108

144

180

216

252

NE-60834

NEVADA 2

5

10

15

20

25

30

35

40

45

50

55

60

65

70

75

80

85

90

95

100

NE-60835

NEVADA 1

4

8

12

16

20

24

28

32

36

40

44

48

52

56

60

64

68

72

76

80

PAT-30001

PATCHI 1

6

12

18

24

30

36

42

48

54

60

66

72

78

84

90

96

102

108

114

120

PAT-30011

PATCHI 1

12

24

36

48

60

72

84

96

108

120

132

144

156

168

180

192

204

216

228

240

UT-50554

UTAH 1

5

10

15

20

25

30

35

40

45

50

55

60

65

70

75

80

85

90

95

100

UT-50564

UTAH 2

5

10

15

20

25

30

35

40

45

50

55

60

65

70

75

80

85

90

95

100

As a general rule, always allow a 20% margin when selecting the driver A32091

Driver ND 20W non IP

A32191

Driver ND 50W non IP

A32291

Driver ND 100W non IP

A32391

Driver ND 150W non IP

A32491

Driver ND 200W non IP

A32591

Driver ND 300W non IP

3

IF THE CUSTOMER WANTS TO USE CV DRIVERS FOR UNDERWATER? • All underwater luminaires already come with remote CC drivers • The underwater luminaires do not have current limiting diodes so cannot be used with constant Voltage circuits today.

WHAT IS VOLTAGE DROP? • Electrical cables are like resistors, the electrons in the copper bounce around preventing the current to travel effectively, see herefor more information • Why is this a problem? If the Voltage drops too low the LEDs will stop working • The resistance of the cable depends on many factors: the quality of the copper, stranded or solid, wire diameter, length, temperature, coiling and its condition • AC Voltage has more Voltage drop that DC Voltage • The Voltage drop can be calculated here • For example, a 1mm copper cable will lose 0.029V over 1m at 24V DC / 700mA

4

WHAT IS THE MAXIMUM VOLTAGE DROP ALLOWED? • “It is recommended that the voltage drop should be less than 5% under the fully loaded condition” • In this case, if we use 24V DC as our standard for LED lighting, the maximum Voltage drop is 1.2V • Typical wiring from a driver to an LED board is around 0.5mm dia(0.25 –1mm is common) • Using the above information, for a 350mA LED, the maximum distance from the driver allowed is 20m. For a 700mA LED, the maximum distance is 10m • Constant current circuits are less affected by Voltage drop because they compensate by increasing the Voltage supplied in order to maintain a constant current, until the maximum power is obtained

CC VS CV DRIVERS Constant Current

Constant Voltage

• LEDs work on constant current • Provides constant lumen output

• Good for unknown quantity of luminaires • Ideal for underwater applications when used with current limiting diodes

• More expensive than constant Voltage circuits

• Susceptible to thermal runaway • Sensitive to Voltage drop

5

WIRING CONSTANT CURRENT AND CONSTANT VOLTAGE CIRCUITS Constant Current luminaires must be wired in series

Constant Current driver 20W500mA 3-57V

Constant Voltage luminaires must be wired in parallel

Constant Voltage driver24V DC20W

6

Maximum length allowed depends on driver power available

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+

+

+

Maximum length allowed depends on number of luminaires, current, temperature etc

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