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How can I connect three 100w lamps to a 300w led driver? Answered

Hello my friend,

Could you explain if is possible to connect 3x lamps of 100w to 300w led driver?

The led driver specification was: constant current, 27-36v, 9A.

The lights:
1x, 27-30v, 3.5A, and
2x, 30-36, 3A.

So, can I connect lamps with differents voltages to this dirver?

If not, is it possible if the voltage of these lamps are the same?

What can I do in this situation? what you sugest?



Thank you for all explanation,

so, I will try Connect it in parallel. But I will not use the 3.5A lamp. But, even if I use the same bulbs I'll need to use resistors?

Yes the resistors regulate the current being supplied. without it they would possibly be destroyed. Go here


Enter the following values in the fields

source voltage enter 36 (max for your power supply)

diode forward voltage enter 33 (you probably dont want to supply the min or max voltage.)

diode forward current enter 3000 (because the calculator is asking for milliamps. 3 amps = 3000 ma

number of LED's in your array enter 3

At the bottom you will get a diagram showing how to wire the circuit along with the required resistor

A good analogy I was taught is this. The current is like water coming full force out of a fire hose. your LED wants a drink of water but imagine trying to drink out of a fire hose. A resistor is like putting a valve on the water hose to bring the pressure down to a level that you can drink from without being injured severely.

If current is additive in parallel wouldn't that mean 3 of the 3A LED's draw a total of 9A which COULD give you the possibilty of over drawing the LED driver because of possible variation in the 9A spec. Where as in serial voltage is additive and current is constant. They would be destroyed becasue the combined current draw is only 3A, however because voltage is additive you would need 90V to power all of them.

If you are concerned about possibly destroying the LEDS, google LED resistor calculator. There are calculators that you can put your exact circuit in and it will give you resistor values

Wire them in parallel and your all set.

No, that will destroy them. The driver is 9A, it will try and push 9A anyway it can. The lower voltage LEDs will have 9A forced through them, and burn out, then the others.

This driver won't suit your LEDS. DO NOT PUT THEM IN PARALLEL. You will destroy them instantly.