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If you have previously been interested in installing LED strip lights in your home or office, you may have heard about the problems that can affect their operation, especially voltage drops.
LED strip lights require a constant voltage to work properly, normally between 12VDC to 24VDC, but sometimes certain situations can arise that affect the power supply. Therefore, when installing LED lightning, it is necessary that you take certain precautions to avoid this problem.
Today, you’ll learn what exactly a voltage drop is, what causes it, and what steps you can take to avoid it.
What Is a Voltage Drop?
Voltage drop is a term used to describe any decrease in supply voltage in an electrical circuit. This term is also often used to describe a voltage loss at some specific point in a circuit, the average voltage loss in the entire circuit, or to give a broad description of the phenomenon of voltage loss in a circuit in general.
Any electrical circuit, however simple it may be, presents a certain level of resistance to the flow of electrical current. This resistance allows the electrical current to work more efficiently by absorbing energy, and this energy loss is what causes the phenomenon known as voltage drop.
You can be better understand this with an example. Imagine you have a simple circuit made up of a 9-volt battery connected to a small flashlight bulb and a small switch. If you were to measure with a multimeter the voltage across the battery terminals with the switch open, the reading would be approximately 9 volts. But if you close the switch to illuminate the bulb, that reading would drop about 1.5 volts.
This voltage reduction is what is known as voltage drop and occurs as a result of the workload that the battery has to illuminate the bulb. Consider that all the components of an electrical circuit, whether they are power supplies, cables or terminals, have a certain level of resistance to the flow of electric current, so they will also have an associated voltage drop.
Its application on various types of devices
In applications that are very sensitive to supply voltage, such as electronic devices, the voltage loss must be calculated very carefully in addition to adjusting the supply voltage, always taking into account the mentioned voltage drops. For example, a 12VDC power supply will usually produce an output of 13.8 volts to combat voltage drops.
On the other hand, those applications that require very long sections of cable, usually require the use of denser cables than normal to present less resistance to the flow of electrical current and try to minimize the effects of voltage drops. This is why it’s so important to carefully calculate the total potential voltage drop during the design and specification phase of any circuit to ensure that the end result works correctly.
In this sense, today it’s possible to calculate with great precision any voltage loss in a circuit using a voltage drop formula. These calculations can vary depending on the type of circuit, voltage supply and components involved, sometimes being very complex calculations, so it is necessary to use a specialized calculator for this purpose. In the end, all these calculations will allow you to obtain more predictable and consistent results when finishing an electrical installation.
What Causes a Voltage Drop?
In general terms, voltage drops are due to the increase in resistance in an electrical circuit, something that normally occurs due to the increase in the energy load on the different components that make up the circuit. To understand this better, let’s look at the factors that can contribute to a greater or lesser extent to the occurrence of this phenomenon.
1. Wrong connection type
Using the wrong type of connection by increasing the wiring distance between a terminal – like LED strip lights – and its power source can cause voltage drops. You can easily see this when using an LED strip lighting installation with a 10m cable that is too thin, which can result in a power supply that is lower than expected.
In this sense, the density of the cable is a key factor when working with very long cable sections; the thickness of the cable must increase in proportion to the increase in the wiring distance to avoid these annoying voltage drops. This factor can also be applied in reverse, as for shorter cable runs, you can use thinner cables and not see significant voltage drops.
2. The type of cable used
The material that the cable you use is made of is also a factor that can affect its performance. Keep in mind that there are many different types of applications for cables, and this determines the material used in their manufacturing process. For example, cables for TV antennas are usually made of copper, while many other applications in the home can make use of aluminum cables. The key factor here is that the better the conductive material, the more efficiently the wire will be able to conduct electrical current.
Now, in the specific case of LED strip lights, LED tape length can also be a factor that causes the appearance of voltage drops. This can happen if the LED tape length is too long, usually exceeding 6m in length.
How Voltage Drops Impact LED Strip Lights?
Let’s take another example. As a general rule, when you have electrically intensive appliances such as washers, dryers or microwaves, all connected to the same circuit and turned on at the same time, the circuit can experience an electrical overload. This situation, if not detected on time, can cause excessive heating of the wiring or other component of the circuit, which can cause it to burn or arc and cause a short circuit, being a potentially dangerous situation that can even end up causing a fire.
In the case of LED strip lights, it just so happens that voltage drops are not necessarily going to damage the LEDs, since in many cases the drops can be due to less voltage than necessary reaching the lights. However, similar to the example in the previous paragraph, a voltage drop implies that a large amount of heat is building up somewhere in the circuit due to electrical resistance.
This situation, in addition to damaging the component that is accumulating all that heat, generally the wiring, if your LED strips are very close to any material that can easily catch fire, this can be a dangerous situation that you should avoid at all costs.
How Can You Fix or Avoid Voltage Drops in Your LED Strip Lights?
Since the main cause of voltage drops in LED strip lights is increased electrical resistance, the best way to avoid this problem is by refraining from passing too much electrical current through a wiring of inadequate length. There are several measures you can take to prevent and solve this problem.
1. Avoid increasing cable length
If you want to avoid using very long cables, the best thing to do is to route the cable so that it passes through walls and ceilings directly, rather than around these structures. Although sometimes, this can also mean that you have to buy more LED light strips anyway and connect them to additional power supplies at different points throughout the building.
2. Use a cable with the correct properties
Contrary to the previous point, if you need to do a very extensive installation using a very long cable that goes from the power supply to the LED strip lights, make sure the cable is long and dense enough to reduce the resistance of the electrical load. To calculate the correct cable length and possible voltage drop, you can use an online calculator.
3. Use shorter LED light strips
One way to decrease the length of your LED light strips is to divide the strips into sections. The most common way is to create two sections of strips by placing the power supply near the center of the room and then dividing the strips equally, but this will also depend on your particular situation. As already explained in the first point, you can also use more LED light strips with additional power supplies.
4. Use 24V light strips instead of 12V
This measure is appropriate when you want to install LED light strips with a length that exceeds 6m (usually more than 10m). This is because on 12V strips, voltage drops are more frequent and faster, so choosing 24V strips is a better alternative, as you will get the same light output, but with half the current.
There are several causes that can lead to a voltage drop in LED strip lights, but as a general rule, this problem is related to the increase in resistance in the electrical circuit, mainly by not using wiring with the appropriate characteristics. Voltage drops are a frequent problem in many types of electrical installations, especially in the home. If the installation is not carried out by a professional, the lack of knowledge and experience can be a factor that influences this type of situation.
The good news is you do not have to be a professional electrician to successfully install LED light strips while avoiding problematic voltage drop. There are simple solutions, as outlined above, that you can apply yourself to prevent this problem from occurring and thus extend the life of your LED strip lights, while avoiding other undesirable consequences. We hope this article has provided you with all the information you need to do so.