Can You Operate a 12V LED Strip at Less Than 12V?

You'll most likely find a specification for DC 12V or DC 24V while looking for LED strip lights. This is the necessary input voltage to run the LED strip light, as you would have guessed.

But what does "required" mean? It should go without saying that supplying more than 12V DC on a 12V LED strip is not a smart idea since you risk over-driving the LED strip and damaging the circuit and on-board components by burning out the diodes or generating an excessive buildup of heat. However, what if we provide 11V or even 9V? Is that "allowed"? Is it bad for the LED?

The simple answer is no, absolutely not. It is entirely legal and safe to use a voltage level that is lower than the specification. Additionally, we conducted some tests to give you some real-world information so you will know what to anticipate if you decide to under-drive your LED strip lights.

Why Does This Matter?

You might be curious as to when an LED strip might be under-driven or if under-driving an LED applies to your specific setup before we discuss our test setup and results.

At the circuit level, LED strips are made to pair with a particular voltage in mind. For instance, the voltage will typically be an exact match when using our 12V and 24V DC power supplies with our 12V and 24V DC LED strips.

Almost all specifications—including those relating to power draw per foot and lumens per foot—assume that the supplied voltage is exactly at the level of the rated voltage. (i.e. 12V DC or 24V DC).

Having said that, it is perfectly safe and legal to supply a lower voltage than the rated voltage in order to under-drive an LED strip. We decided to conduct our testing because the majority of LED strip manufacturers do not offer any information on how and to what extent under-voltage impacts LED strip performance. Our test results provide some useable, preliminary estimations.

You can have a power supply voltage that is lower than the LED strip voltage standard in one of three different circumstances. The first is a deliberate decision to use a lower voltage in order to produce a lighter output than the rated output. For instance, you might decide that 450 lumens at 5.5 watts per foot is too high for your requirements and that 2.3 watts per foot is a better operating level for the LED strips. Without having to buy and install a dimmer, using a 20V power source on a 24V LED strip would be an easy and efficient way to accomplish this.

The second circumstance might result from limitations in the current system. The power supply voltage may fall below 12V DC when the system discharges, for example, if you want to mount your LED strips on a battery system. If and when the supply voltage falls below the LED strip's rated voltage, the information in the table below should be helpful in predicting the level of power consumption you can anticipate.

The third condition might be caused by insufficient wire gauge and resulting voltage drop. The voltage level may drop before the copper wire even starts to power the LED strip when too much current flows through a long piece of copper that isn't thick enough.

Setup for our test

We connected a benchtop power supply to a 1-ft (30 cm) section of our Ultra High 95 CRI LED strip lights. We measured the current draw as a function of input voltage, in 0.1V increments, for the benchtop power supply, which has a variable input voltage capability.

Both the 12V and the 24V versions of this test were conducted again.

Prior to reducing the voltage in 0.1V steps and measuring the current draw, we first measured the current draw at each device's rated voltage.

Important: keep in mind that only our own LED strip lights were tested to provide these findings. Results will differ among different goods and manufacturers.

General Takeaways from Our Test Results

What we first notice is that the LED strips do not light up until a minimal threshold voltage. For 12V LED strips, this is roughly 7.5V, and for 24V LED strips, it is 15.5V. This is a bit counter-intuitive, since this implies that you cannot simply expect a 6V power supply input on a 12V LED strip to simply produce half the power.

After reaching this minimum threshold voltage, power consumption for 12V and 24V LED strips, respectively, rises by approximately 1.0 watts per foot for every 0.75 volt and 1.5 volt increase in voltage.

If you're in a bind and that's the only power source you have on hand, you could find these results helpful since that voltage level is a common one for laptop power supplies. According to our findings, a 19.5V DC input will give a 24V DC LED strip a power level of roughly 2.0 watts per foot, which is a quick and simple approach to purposefully limit light output by about 60%.

Downsides to Under Voltage Operation

In addition to being perfectly safe, under-driving LED strips by applying a voltage lower than their rated voltage has no negative consequences on the LEDs or the circuitry, as was already mentioned.

If anything, by driving them below their rated current, the LED strips' projected lifetime and longevity will be much longer.

From a technical sense, there truly aren't any negatives. From a practical perspective? The only downside would be the fact that you are in a way over-paying for power capacity.

A decent quality LED strip is meant to comfortably offer a particular degree of brightness, and it consequently is constructed with the proper number of LEDs per foot, as well as adequate copper thickness to manage the power. This necessarily implies you are spending more for higher quality and quantity parts and materials, but because you are using them to a lesser level, you are not getting the most out of them. You could compare it to purchasing a sports car but only using it for 50 mph driving.

12 Volt 5 Watt Led Bulb

Feature

● They do not have any polarity problem(s to avoid damage due to an incorrect connection)

● 80% energy savings compared to filament lamps

● Can be connected directly to 12V batteries

● A large number of on / off cycles

● Ease of installation with E27

● Low operating temperature

● High lightness

● Stable and compact design

● CE and ROHS certificates

Specification