Making Certain of LED Driver CompatibilityMarch 9, 2017
One of the most important aspects of specifying LED lighting is to verify LED driver compatibility. There are over a dozen major LED manufacturers plus many smaller suppliers and each has its own requirements. Additionally, there's the need to consider the range of potential driver configurations, AC supply voltage, the number of LEDs controlled by each driver, and whether to include the ability to dim LEDs.
Single or Multiple LED systems
Apart from single LEDs that are designed as a direct replacement for conventional Edison screw bulbs used in domestic fittings, many variations are possible. LEDs may be installed on their own, in banks, or in groups using either series or parallel connections, or even a combination of both. Consequently, a LED driver may have to supply power to one or many LEDs. Before you establish LED driver compatibility, consider the number of LEDs that will be controlled by each LED driver along with the current and voltage requirements of the LED array. Another important aspect is the volt drop across an array, especially when individual LEDs are spaced well apart.
Constant Current or Constant Voltage
You need to decide if the LED driver should have a constant current or constant voltage characteristic. Normally, a constant current driver is needed because the light output of LEDs is proportional to current. A constant current driver ensures consistent brightness. Be aware that LED current is highly sensitive to the applied voltage. A small increase in voltage causes a big change in current. Apart from brightness fluctuations, excessive current causes damage to LEDs.
LED manufacturers sometimes string several LEDs together to form a strip light. In this case, they usually fit a current limiting resistor to restrict the maximum current. These strips are designed for operation at a fixed voltage and consequently need a constant voltage LED driver.
To Dim or Not
LED light output is proportional to current, so it's possible to dim LEDs. Benefits of dimming LEDs include:
- Reduced energy usage: Energy consumption is proportional to light output.
- Increased life: LEDs last longer if they are dimmed.
- Improved comfort: Lighting levels can be adjusted to suit individual preferences.
- Adjust ambiance: Create the right mood by dimming lamps.
- Facilitate audio visual presentations: Dim the lights when using overhead projectors in board rooms and theaters.
- After hours: Dimming lighting after hours saves energy.
To simplify LED driver compatibility, manufacturers design their LEDs to conform to certain criteria. Parameters include:
- Maximum current
- Maximum voltage
- Power input
- Light output
- Color temperature
- Heat loss
While specifications between various manufacturers may have similarities, there will be detail differences due to different design and manufacturing techniques. When selecting LEDs from different manufacturers, you need to take these differences into account. To ensure LED driver compatibility, you need to consult suppliers' catalogs to check LED manufacturer specifications. This is one reason why it's important to buy LEDs from well-known, reputable manufacturers, rather than discount stores. Another way to establish LED driver compatibility is to contact LED driver manufacturers who may publish compatibility data.
Not All LED Drivers Are Created Equal
The selection of LED drivers needs to be made with care. For starters, each LED manufacturer has its own prerequisites. Secondly, there are many possible LED permutations. ERP Power's design team understands this, and their extensive range of high-quality LED drivers caters for every eventuality.