What is an LED Driver?
An LED Driver is a device that does exactly what it sounds like – It drives electric power to one or more LEDs. More specifically, it distributes a constant and consistent flow of electrical current at all times – which LEDs require. LEDs do not require a large amount of power to get them going, which makes them very energy efficient. They actually work on DC power at a rather low voltage. Because of this, they need something that will convert AC into DC, and feed them just the right amount of electrical current and voltage that they require. Doing this allows the LEDs to stay a consistent temperature. If an LED runs too hot, it may begin to malfunction and experience poor performance. The LED Driver acts not only as an electrical current management system, but also as a protective buffer from power surges that may occur. LED Drivers are a diverse group of products depending on their intended use. You’ll notice there are primarily two distinct types – Constant Voltage and Constant Current. Both versions serve different functions in different situations, so it is important to determine the product specifications of your LED lamp to make sure you are using the correct type. They are not interchangeable.
If you have questions or aren’t quite sure which LED Driver you need, give us a call toll-free at 1-877-775-2852 or 775-826-6222 and one of our lighting technicians will be more than happy to help you find what you need.
Differences between Constant Voltage and Constant Current LED Drivers:
Constant Voltage LED Driver:
A Constant Voltage Driver is used for LEDs that require a steady and constant DC voltage to keep them performing well. Most often constant voltage is used with an LED device that has a built-in proprietary driver that already manages the operational current. The Constant Voltage Driver is only used to keep the voltage consistent. It is also mainly for applications where the LEDs are in a strip configuration and in a parallel connection to the driver. It ensures that every LED receives the same amount of voltage from the driver. LEDs often use Constant Voltage Drivers for landscape lighting, accent lighting for works-of-art, and back-light for advertising signs.
Constant Current LED Driver:
Rather than regulating voltage, a Constant Current Driver manages the actual current that is required to get things jumping. Additionally, this type of driver regulates forward current that occurs between LEDs. Too much of this forward current can potentially overheat the LED. Constant Current Drivers are more commonly used in commercial applications that deal with LED clusters mounted on a PCB (Printed Circuit Board) – either in series and/or parallel. These types of PCB assemblies are most commonly used in high power LED fixtures such as LED Wall Packs, LED Cobra Heads and LED Flood Lights. These types of fixtures require high-powered external LED drivers to regulate the operational current. The higher the current, the brighter the LED. If this current goes unregulated, it will cause the LED to draw current above the manufacturer’s specifications – which will increase the operating temperature and eventually the LED will fail. A Constant Current LED Driver usually has a fluctuating voltage output and will operate within that range. For example; If a driver with a range of 27 to 48 volts output current is predetermined and maintained at 1,400mA (or 1.4A), the driver will power up a fixture in the range of 37.8 to 67.2 watts.
Both Constant Voltage and Constant Current LED drivers can be dimmed. There are a number of ways to dim the LED drivers depending on the application or the specific customer request.
Triac Dimming or Phase Cut Dimming:
This method of dimming is generally associated with Constant Voltage Drivers. It’s a common system that can be used with readily available LED-compatible dimmer switches. No special wiring is needed for this type of dimming.
Widely used in retail and commercial applications, these drivers are specifically manufactured and equipped for this manner of dimming by providing another set of wires from the dimmer itself which connect to a special 0-10V dimmer switch. This method of dimming is popular because it can control a multitude of fixtures with one switch – regardless of the amount of wattage in play.
Additional Dimming Processes:
Some other dimming methods are known as PWM & DMX. New technologies are also emerging with Bluetooth dimming rising in popularity.