Power requirements for LED tapes are typically 12V, 24V, or 36V. LED strip lighting installations require one or more electrical transformers to reduce the input voltage to the appropriate power level from the 220V–240V range supplied by the country’s main electricity grid.

An LED power supply is a device that converts high-voltage AC power to low-voltage DC power that is suitable for powering LED lights. It typically consists of a power transformer, rectifier, and voltage regulator. LED power supplies provide a stable and consistent output voltage to ensure that the LED lights function correctly.

There are two types of LED power supplies: constant-current and constant-voltage, which are chosen depending on the specific LED lighting system being used.

There is a wide variety of sizes and styles to choose from in our selection of LED drivers and transformers, all of which are available in either 12V or 24V configurations. The length of each LED strip that can be powered (its output wattage) is set by the company that made it.

While any InStyle LED transformer will work with LED tape lights or any other LED product, selecting a type whose voltage and power are compatible with your LED tape is essential.

What is an LED driver? 

LEDs, or light-emitting diodes, are becoming more popular because they last a long time and use little energy. This is because energy restrictions are getting stricter. Many people, however, need to be made aware that unique tools, known as LED drivers, are required to operate these cutting-edge light sources. LED drivers (or LED power supplies) are the electronic devices that supply electricity to LEDs, much like fluorescent lamp ballasts or low-voltage light bulb transformers. The use of LEDs necessitates drivers for two reasons:

  1. LEDs can only be powered by low-voltage (12-24V), direct-current energy. However, greater voltage (120-277V) alternating current energy is available in most locations. An LED driver converts alternating current at a lower voltage into direct current at a greater frequency.
  2. The LEDs they power are shielded from any sudden changes in voltage or current by the drivers. The current flowing through the LEDs may shift as the voltage shifts. The brightness of an LED is directly related to the amount of current it receives; therefore, LEDs can only safely run within a limited current range (measured in amps). Thus, the excessive or insufficient current might cause the LED to overheat, leading to diminished light output or accelerated degradation. LED drivers change the alternating current from a higher voltage to a lower voltage that LEDs may use. They also maintain the LED circuit’s voltage and current at optimal levels.

Internal vs. External Drivers 

This is why a driver is necessary for every LED light bulb. But some LEDs, especially those made for home use, have drivers built in, so they don’t need a separate power source. Also, most home light bulbs have a built-in motor that makes it easy to switch from incandescent to compact fluorescent or vice versa. This category includes LED bulbs with a common screw-in or plug-in base or line voltage (120 volts) as an input on their datasheet.

  • Cove lights, 
  • Downlights, 
  • Tape lights, 
  • Fixtures, 
  • Panels, 
  • Outdoor-rated lights, 

An external driver generally demands these. Commercial, outdoor, and street lighting use these lights frequently. Because it’s easier and less expensive to replace the driver than the LEDs, they often need to be wired to a separate power source. 

LEDs may sometimes have a built-in driver. Sometimes the manufacturer’s datasheet for an LED will state whether or not an additional driver is required and, if so, what kind of driver is needed.

To extend the life of LEDs, swap out their external drivers. When an LED fails to light up before the end of its expected lifespan, it is often salvageable by replacing the driver. Overheating causes premature failure in several drivers. Electrolytic capacitors, which resemble batteries, are a common cause of mortality. When an electrolytic capacitor is used, a gel inside evaporates over time. This makes the capacitor less able to store energy.

Due to how quickly the gel evaporates and how short the capacitor’s life is, leaving the driver and LED in a hot car may suddenly stop working. Both the temperature on the inside and outside of the driver case are proportional to each other. Therefore, on the label of most LED drivers is a little circle representing the driver’s hottest spot, the “TC point.” Most of the time, this is a temperature indicator that shows the driver’s safest operating temperature.

Let’s say you run a driver dangerously close to the highest temperature it can handle. It will only last as long as you run it at a lower temperature. Because of this, drivers with a higher total TC score tend to last much longer. So that the driver lasts longer than the LEDs, it needs to work at temperatures below the TC point. If an LED doesn’t meet one of these requirements, the driver could fail and need to be replaced.

What Is An LED Power Supply

How to choose an LED Driver 

In addition to discussing the two most common kinds of external LED drivers—constant-current and constant-voltage—we’ll also talk about the third kind of driver, an AC LED driver. Different LEDs have various electrical needs; hence, different drivers are needed to power them. To avoid problems, a new driver should have input/output specifications almost identical to those of the outgoing one.

Key differences are detailed below. 

  • Constant-Current Drivers: LEDs with specific current and voltage requirements can be driven by constant-current drivers. The LED’s load (wattage) will determine the voltage range accompanying the single output current specified in amps or milliamps. As you can see in the image to the left, the output voltage ranges from 4-13V DC at a current of 700mA.
  • Constant-Voltage Drivers: LEDs that operate at a constant current up to a fixed voltage are powered by constant-voltage drivers. This type of LED already has current regulation built in through resistors or a constant-current driver. These LEDs need a constant 12V DC or 24V DC voltage. 

AC LED Drivers 

Because LED drivers are no-minimum-load transformers, they can power other low-voltage bulbs besides LEDs. However, standard transformers aren’t equipped to handle LEDs because of their low power. In other words, ordinary transformers do not recognize that they are linked to an LED bulb because of the low electrical demand that LEDs produce.

An AC LED driver detects low-wattage LEDs and decreases the voltage to 12 or 24 volts. The bulb’s internal driver converts AC to DC; therefore, the AC LED driver steps down the voltage.

Although 12-24V AC input LED MR16 bulbs are the most common users of AC LED drivers, these devices are compatible with any LED bulb that requires a 12-24V AC input voltage. However, if the LED bulb specifies a DC voltage input, it cannot be utilized with an AC LED driver, and vice versa.

Other Factors to Consider 

Max Wattage 

To follow the NEC, you must use LED drivers with LEDs that use 20% less power than their maximum wattage. To prevent the driver’s components from being overworked, you should not use it with an LED whose wattage is equal to or greater than the driver’s maximum wattage. For instance, if your driver has a maximum wattage output of 96, you should only use LEDs with a maximum wattage consumption of 77 (96 * 0.8 = 76.8).

Dimming 

Both constant-current and constant-voltage designs can have LEDs and drivers that can be dimmed. However, the LEDs and drivers must be named on the product datasheet for both designs. For example, if the specifications say nothing about dimming, it cannot be dimmed. But some external drivers can be turned down with a special dimmer or other devices that control the amount of light they put out.

Due to the rapid development of new technologies, it is recommended that customers conduct dimmer performance tests on individual LED and dimmable driver combinations before making large orders.

Power Factor 

The power factor measures an LED driver’s efficiency. Watts measures how powerful a driver is, while the power factor is the input voltage divided by the input current (volts by amps). The power factor ranges from 0 to 1, and closer to 1, the motor’s efficiency increases.

A power factor of 0.9 or higher is ideal. Comparing UL Class 1 and UL Class 2, Drivers classified as UL Class 2 by UL meet the requirements of standard UL1310, which means that you can touch the output without risk, and further safety measures are not needed for the LED or light fixture. No danger of fire or electric shock exists.

These drivers can run on as little as 30 volts in wet environments and as little as 60 volts in dry ones, as well as less than five amps and 100 watts. But because of these constraints, a Class 2 driver can only power many LEDs. As a result, the output ranges of UL Class 1 drivers exceed those of UL Class 2 drivers. Due to the high voltage output of a UL Class 1 LED driver, additional in-fixture safety measures are required. Class 1 drivers are more efficient since they can power more LEDs than Class 2 drivers.

Ingress Protection (IP.) Rating 

From the IP rating, users can find out how well a driver’s case protects the environment. The first number shows how well it can handle the dry matter, and the second shows how well it can handle the wet matter.

  • Able to withstand impact from items up to 50 mm in diameter, like an accidental bump of the hand 
  • Safe from the dangers of water dropping from the ceiling
  • Safe from projectiles larger than 12.5 millimeters in diameter, like fingers
  • It may be inclined vertically by up to 15 degrees without being harmed by water sprays.
  • Secure against projectiles with a diameter of more than 2.5 millimeters, like tools and wires
  • It may be tilted up to 60 degrees vertically without being harmed by water sprays.
  • Safe from projectiles larger than 1 mm in diameter, like small wires.
  • Safe from water coming from all sides is covered to keep out the dust
  • Safe from water squirting in from any direction at low pressure
  • Airtight dust (total protection)
  • Safe from water that can slam in from any direction
  • Waterproof during brief submersion (under 30 minutes)
  • Safe from the effects of prolonged submersion in water. 

Security

Safety should be the top priority when analyzing a driver and their lighting system. A line-powered LED driver with 1500 V RMS (50 or 60 Hz) dielectric isolation from input to output is preferred. Input or output isolation requires a transformer with galvanically isolated primary and secondary windings. IEC 61140 requires that the output voltage is below 60 VDC. More LED lighting products use a non-isolated topology to minimize costs. LED products with low-cost linear regulators provide a shock hazard. The inputs and outputs of these circuits are separate, so you may need to check the electrical insulation of the lighting systems.

AC-powered systems require creepage and clearance distances. Electrocution or fire can result from improper creepage distance between primary and secondary circuits. Clearance, the shortest distance between two conducting parts, must be considered to prevent air-ionized electrode arcing. A good PCB design is needed to avoid EMI emissions, creepage, and clearance issues as electronic circuits get smaller.

All electrically conductive and touchable LED driver elements must be connected to the ground. Class II LED drivers operate residential and commercial LED lighting systems. Therefore, class II LED drivers do not require enclosure grounding. Still, all internal conductors must be double- or triple-insulated to keep the mains power circuit from interfering with the output side of the driver or its metal casing.

Temperature

An LED driver changes the AC line voltage into DC output as efficiently as possible, turning lost energy into heat. For example, a 90% efficient LED driver needs 111 W to drive a 100 W load. As a result, 11 W of input electricity becomes heat. This stresses the LED driver circuit thermally. In addition, when the driver is in the luminaire housing, the LEDs’ thermal load raises the driver’s temperature. 

The driver must use high-temperature components and remove heat from thermally sensitive components. Excess heat causes component reliability difficulties, including dried-out electrolytic capacitors. Therefore, an LED driver’s operating temperature determines its lifespan. High-wattage LED drivers use aluminum enclosures with high-density fins and thermally conductive grouting to dissipate heat.

IPS

LED drivers for road, street, exterior, and landscape lighting must be sealed to prevent dust, water, and other items from entering. Indoor applications, including carwashes, cleanrooms, bottling and canning operations, food processing facilities, pharmaceutical industries, or any industrial application needing frequent high-pressure wash downs, require LED drivers with high ingress protection (IP). Self-contained LED drivers for wet situations are frequently potted in silicone to improve enclosure integrity and electrical insulation. These drivers are IP65, IP66, or IP67.

Placement

LED drivers can be put in from a distance or inside the lamp or luminaire housing. In non-DOB co-located systems, the driver must always be thermally insulated from heat-generating LEDs. Housing design should consider driver upkeep. Long-distance PWM drivers in remote-mounted devices can lose performance. Remote-mounted systems favor CCR dimming.

Is a constant-current driver the same as a resistor? 

In the sense that they both control electrical current, yes. On the other hand, a resistor will slowly make the current go up over time. Constant-current drivers are best for high-power LEDs because they are reliable, efficient, and flexible.

Can you use one driver for multiple LED lights?

A single external driver may be able to power many light sources. Therefore, the maximum number of lights a certain driver can control should be listed on its datasheet.

What is the difference between Triac dimming and 10-volt dimming?

The TRIAC is the most popular and economical option for dimmers. They do, however, cause excessive electromagnetic interference (EMI). Although more expensive than TRIAC dimmers, trailing edge or ELV dimmers produce substantially less electromagnetic interference (EMI).