Skip to main content
Electrical Engineering

Return to Question

Tweeted twitter.com/#!/StackElectronix/status/508264253078241280
more precise data
Source Link
Alex Okrushko
Alex Okrushko
  • 145
  • 2
  • 8

I have a lamp that has LED driver producing 35 V (actually lamp driver says 1516 - 2528 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.

LEDs specs:

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Current (IF) : 700mA
  • Color Temp: 6000~6500K (white)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

So I've figured out:

$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

LED DRIVER

Actual current max reading

I have a lamp that has LED driver producing 35 V (actually lamp driver says 15 - 25 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.

LEDs specs:

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Current (IF) : 700mA
  • Color Temp: 6000~6500K (white)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

So I've figured out:

$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

LED DRIVER

Actual current max reading

I have a lamp that has LED driver producing 35 V (actually lamp driver says 16 - 28 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.

LEDs specs:

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Current (IF) : 700mA
  • Color Temp: 6000~6500K (white)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

So I've figured out:

$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

LED DRIVER

Actual current max reading

added 146 characters in body
Source Link
Alex Okrushko
Alex Okrushko
  • 145
  • 2
  • 8

I have a lamp that has LED driver producing 35 V (actually lamp driver says 15 - 25 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.

LEDs specs:

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Current (IF) : 700mA
  • Color Temp: 6000~6500K (white)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

So I've figured out:

$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

LED DRIVER

Actual current max reading

I have a lamp that has LED driver producing 35 V (actually lamp driver says 15 - 25 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.

LEDs specs:

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Current (IF) : 700mA
  • Color Temp: 6000~6500K (white)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

So I've figured out:

$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

I have a lamp that has LED driver producing 35 V (actually lamp driver says 15 - 25 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.

LEDs specs:

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Current (IF) : 700mA
  • Color Temp: 6000~6500K (white)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

So I've figured out:

$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

LED DRIVER

Actual current max reading

Changed multiplication symbol in expressions an fixed list formatting (specs)
Source Link
Ricardo
Ricardo
  • 6.2k
  • 20
  • 54
  • 89

I have a lamp that has LED driver producing 35 V (actually lamp driver says 15 - 25 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.
LEDs

LEDs specs:
LED Emitter: 3W

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward CurrectCurrent (IF) : 700mA
  • Color Temp: 6000~6500K ( Whitewhite)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

soSo I've figured out:

$$R=\frac{V_{Driver}-V_{LED}*7}{I_{LED}} = \frac{35\ V-3.7\ V * 7}{0.7\ A} = 13\ \Omega\ $$ which$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

I have a lamp that has LED driver producing 35 V (actually lamp driver says 15 - 25 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.
LEDs specs:
LED Emitter: 3W

  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Currect (IF) : 700mA
  • Color Temp: 6000~6500K ( White)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

so I've figured out:

$$R=\frac{V_{Driver}-V_{LED}*7}{I_{LED}} = \frac{35\ V-3.7\ V * 7}{0.7\ A} = 13\ \Omega\ $$ which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

I have a lamp that has LED driver producing 35 V (actually lamp driver says 15 - 25 V, but I've measured 35 V). On the lamp I have 7 LEDs (originally 5 + 2 I've added) with heatsinks that have burned and replaced a couple of times now. All LEDs are connected in sequence.

LEDs specs:

  • LED Emitter: 3W
  • Output Lumens: 180-210 Lumens
  • DC Forward Voltage (VF) : 3.6-3.8Vdc
  • DC Forward Current (IF) : 700mA
  • Color Temp: 6000~6500K (white)
  • Beam Angle: 120 degrees
  • LifeSpan Time : > 50,000 hours

So I've figured out:

$$R=\frac{V_{Driver}-V_{LED} \times 7}{I_{LED}} = \frac{35\ V-3.7\ V \times 7}{0.7\ A} = 13\ \Omega\ $$

which is nothing. At the same time my LEDs are burned down within a month.
What am I doing wrong?

Source Link
Alex Okrushko
Alex Okrushko
  • 145
  • 2
  • 8