Triac Dimmable LED Driver

Frequently Asked Questions

What is a Triac dimmable LED driver?

A Triac dimmable LED driver is a constant voltage power supply that converts mains AC voltage (200–240V) to a stable DC output while supporting Triac phase-cut dimming. It allows you to control the brightness of your LED strip lighting using a standard wall-mounted Triac dimmer switch, delivering smooth 0–100% flicker-free dimming without the need for additional control wiring. Our Triac dimmable LED power supply range is available in both 24V and 48V output voltages, from 80W up to 600W, covering everything from smaller residential installations to large-scale commercial and architectural projects.

What is the difference between a 24V and 48V Triac dimmable LED driver?

Both our 24V Triac dimmable driver and 48V Triac dimmable driver deliver reliable constant voltage output with full Triac dimming compatibility, but each suits different installation requirements:

• 24V Triac Dimmable Driver: The most widely used voltage for LED strip lighting. Compatible with the broadest range of 24V LED strips, controllers and accessories. Ideal for residential, hospitality and commercial installations with standard run lengths.
• 48V Triac Dimmable Driver: The preferred choice for longer runs, higher power density installations and professional projects where voltage drop must be minimised. 48V systems draw half the current of 24V for the same wattage, allowing longer cable runs with consistent brightness and reduced wiring costs.

If your installation requires runs longer than 10–15 metres from a single feed point, or you are working with high-wattage LED strip, the 48V Triac dimmable power supply is generally the better specification choice.

What dimmer switches are compatible with a Triac dimmable LED driver?

Our 24V and 48V Triac dimmable LED drivers are compatible with both leading edge and trailing edge Triac dimmers, working seamlessly with dimmer switches from leading brands including Lutron, Legrand, Crestron and Leviton. Key compatibility considerations:

• Leading Edge (Forward Phase): The older, more common Triac dimming method found in most existing installations — fully supported by our drivers.
• Trailing Edge (Reverse Phase): Smoother, quieter and better suited to modern LED loads with less electrical noise and a cleaner dimming curve — also fully supported.
• Load Rating: Always check that your dimmer's minimum and maximum load rating matches your driver wattage to avoid flickering or instability.
• LED-Rated Dimmers: Always use a dimmer switch specifically rated for LED loads rather than a legacy incandescent dimmer.

For new installations, trailing edge dimmers are generally recommended for the best dimming quality. If you are unsure about compatibility, contact our technical team before purchasing.

How do I calculate the right wattage for my Triac dimmable LED driver?

Selecting the correct Triac dimmable LED power supply wattage is straightforward:

• Step 1: Find the wattage per metre of your LED strip (printed on the strip or packaging, e.g. 14.4W/m)
• Step 2: Multiply by total length in metres (e.g. 15m × 14.4W/m = 216W)
• Step 3: Add a 20% safety buffer to protect longevity and ensure stable dimming (216W × 1.2 = 259.2W)
• Step 4: Select the next driver size up — in this example, a 300W driver

For installations with multiple strips, add all individual wattages together before applying the safety buffer. Never run a Triac dimmable driver at full capacity as this reduces lifespan and can cause unstable dimming behaviour at the lower end of the range. This calculation applies equally to both our 24V and 48V Triac dimmable drivers.

Why are my LED lights flickering with a Triac dimmable driver?

Flickering with a Triac dimmable LED driver is one of the most common installation issues and is almost always caused by one of the following:

• Incompatible Dimmer: The dimmer switch is not rated for LED or electronic low voltage loads — replace with an LED-compatible Triac dimmer.
• Load Below Minimum: Total LED wattage falls below the dimmer's minimum load rating, causing instability — check the dimmer's minimum load specification.
• Overloaded Driver: Combined strip wattage exceeds the driver's rated output — size up to the next wattage.
• Long Cable Runs: Excessive cable length between the dimmer and driver can introduce interference — keep cable runs as short as possible.
• Poor Connections: Loose or poorly made wiring connections cause intermittent flickering — inspect and re-terminate all connections.

If flickering persists after checking the above, contact our technical team with your dimmer model, driver wattage and LED strip specification and we will diagnose the issue.

What is the difference between leading edge and trailing edge Triac dimming?

Both methods are fully supported by our 24V and 48V Triac dimmable LED power supplies:

• Leading Edge (Forward Phase): Cuts the front of the AC waveform. The older, more widely installed technology found in most existing dimmer infrastructure. Can occasionally cause a slight buzz in LED drivers at lower dim levels.
• Trailing Edge (Reverse Phase): Cuts the rear of the AC waveform. Generally smoother, quieter and better suited to modern LED loads, producing less electrical noise and a cleaner dimming curve.

For new installations, trailing edge dimmers are recommended for the best dimming quality with both 24V and 48V LED strip lighting.

Can I connect multiple LED strips to one Triac dimmable driver?

Yes, multiple LED strips can be connected to a single Triac dimmable LED driver provided you follow these guidelines:

• Total Wattage: The combined wattage of all strips must not exceed 80% of the driver's rated output capacity.
• Wiring Method: Always wire strips in parallel, not in series, to ensure each strip receives the correct supply voltage.
• Balanced Distribution: For best dimming consistency, position the driver centrally and use equal-length output cables to each strip.
• Voltage Drop: For longer output cable runs, use a larger gauge cable to minimise voltage drop — particularly important on 24V systems. Our 48V Triac dimmable driver range offers a significant advantage here, as the higher voltage means far less voltage drop over distance.
• Connection Organisation: Use a distribution block rather than splicing wires for clean, reliable and serviceable connections.

Available from 80W up to 600W in both 24V and 48V, our Triac dimmable driver range gives you the flexibility to power single strips or large multi-zone installations from one unit.

Are Triac dimmable drivers suitable for outdoor use?

Yes. Our 24V and 48V Triac dimmable LED drivers carry an IP66 rating, making them fully suitable for dry, damp and wet locations. IP66 means the housing is completely dust-tight and protected against powerful water jets from any direction, making them a reliable choice for permanent outdoor LED installations including:

• Garden and decking lighting
• Building façade and exterior architectural lighting
• Landscape and pathway lighting
• Pergola, gazebo and covered outdoor structures
• Outdoor hospitality and entertainment venues

Always ensure cable entry points and output connections are properly sealed and weatherproofed when installing outdoors to maintain the IP66 protection of the overall installation.

What protection features do Triac dimmable drivers include?

All our 24V and 48V Triac dimmable LED power supply units include comprehensive built-in protection for long-term safe and reliable operation:

• Overload Protection: Automatically limits output current if the connected load exceeds rated capacity, protecting both the driver and connected LED strips.
• Over-Temperature Protection: Thermal shutdown activates if the driver exceeds safe operating temperature, with automatic recovery once cooled.
• Short Circuit Protection: Safely shuts down output in the event of a short circuit with automatic recovery once the fault is cleared.
• Isolated Design: Galvanic isolation between input and output provides an additional layer of electrical safety, reducing shock risk and improving system stability.

What safety certifications do your Triac dimmable drivers hold?

Our 24V and 48V Triac dimmable LED drivers carry CE, RoHS and REACH certifications, ensuring full compliance with UK and European safety, electromagnetic compatibility and environmental standards. The IP66 rating is independently verified for dust and water ingress protection. All drivers come with a 3-year warranty as standard, with our UK-based technical team available to support installation queries and troubleshooting throughout.

Can I use a Triac dimmable driver with a different voltage LED strip?

No. Always match your Triac dimmable LED driver output voltage precisely to your LED strip voltage. Connecting a 24V Triac dimmable driver to a 12V strip, or a 48V Triac dimmable driver to a 24V strip, will immediately damage the LEDs due to overvoltage. Constant voltage LED drivers do not automatically adapt their output to match the connected load. If your installation requires multiple voltages, always use a dedicated driver for each voltage. If you are unsure which driver is correct for your LED strip, check the voltage marking printed on the strip backing or contact our team for advice before installation.