LED lights require a certain voltage, such as 24 or 12V. When they run at higher voltages, they become extremely hot. Extreme heat damages the LED lights or the soldering around them. Due to the heat damage LED lights start to dim, flicker, or may die entirely.
Increasing heat from power dissipation causes a failure of the LED die. The change in colour, e.g. red and green LEDs going yellow at high currents, is probably because the die is actually glowing hot, i.e. near failure.
So anything from about 4.5 to 5.5 Volts is safe for these LEDs and 6V is the 'rated absolute maximum'. Any higher and they'll burn out quickly.
Quite intuitively, providing more than 12V DC on a 12V LED strip is not a good idea, because you may cause the LED strip to be over-driven, burning out the diodes or causing excessive heat buildup that can damage both the circuit and on-board components.
Going the other way - 24V LED strips on a 12V power supply
If you're trying to go the other way and connect a 12V power supply to operate 24V LED strips, unfortunately, you are out of luck. You'll need to purchase a transformer or voltage booster, or, more straightforwardly, a 24V power supply.
Common led strips take about ~18mA at 12V per segment (typically 3 LED). They are used in Automotive 12V rails, which is 12V nominal, but can go to 14V regularly, with larger spikes.
You cannot run 240v lights on 12v. You can, however, run 12v lights on 12v. The aim seems to be to run safe voltages into your garden. You can connect some of these in series to raise the voltage, but I would strongly recommend not exceeding 3 in series, for 36v supply.
Voltage that is too high can cause premature failure of electrical and electronic components (e.g. circuit boards) due to overheating. The damage caused by overheating is cumulative and irreversible.
Unlike incandescent light bulbs, LEDs don't produce light using heat. This is part of what makes them so energy efficient. The downside is that their components can be sensitive to overheating, which can cause them to burn out prematurely.
I contacted the manufacturer of this light to see if running the light on a 6 volt system would damage the light or reduce life expectancy. He stated that running at reduced power will dramatically reduce the life expectancy of the light because the LED bulbs are designed to be ran at 12 to 14 volts.
An LED with a product label stating “120V-240V” will accept any one of these three voltages 120, 208 or 240 and will automatically sense the supplied voltage to ensure the same output to the LEDs, regardless of the input voltage.
You cannot safely power most LEDs with a 3.3V source when the source can supply more current than the LED's capacity. Two characteristics of the LED need to be known to calculate the resistor. If the current output of the 3.3V source is less than the LED's maximum, then it is safe.
Unlike typical low-voltage lighting products, getting the voltage slightly wrong in an LED-based system is a bigger problem for the LED. Because LEDs are extremely sensitive to under- or over-voltage, you must calculate voltage drop carefully and correct for it.
You have a 12 V supply and each LED might need up to 3.5 V. (12 V)/(3.5 V) = 3.4 LEDs max. Since you can only have whole LEDs, the answer is 3.
The National Electrical Code allows up to a 5% drop. There can be a <3% drop in a feeder and an additional <3% drop in individual branch circuits.
If you find that the voltage at your wall outlets is consistently around 124 VAC or higher, then you have too much electricity in your house and you are using and paying for significantly more energy than your appliances need to use.
The easiest way is to look it up in the datasheet, or the store where you bought it. Look for LED forward voltage and the Test Current. You could find the LED voltage by using a multimeter with a diode function. You could connect a battery to the LED and a potentiometer.
All LED strips, whether 12V or 24V, offer exceptional efficiency and brightness within a low profile. If you still have questions, read below for more technical information. Learn the basic components that make strip lights work and how voltage may affect performance.
24V is better suited for LEDs.
It is through configuring the LEDs in a particular parallel vs series combination, that the voltage of an LED system can be made to match a particular power supply voltage. Typically, a 12V LED strip is configured with 3 LEDs in series per string.
In electrical terms, we now know that at 12V, this LED strip will draw about 24 Watts per reel (5 meters), or about 2.0 Amps.
Your 18V battery probably ranges from about 15V to 21V (flat to fully changed) so it is perhaps ideal for 12V LED modules.
A 5V LED must not be run on 12V.
The answer is “Yes”. A 12V strip can run on a power supply a little lower than its required electrical voltage, like a 9V alkaline battery. This setup is even entirely safe to operate.