Who This Is For (and Why You Might Be Here)

If you're retrofitting a set of floodlights for a parking lot, wiring up a custom tree chandelier for a wedding venue, or trying to figure out why your new recessed lights keep flickering after a bulb swap—this checklist is for you.

I'm the guy who gets the call when the first batch of drivers didn't work. In my role coordinating power supply specs for lighting projects, I've handled roughly 400+ fixture-to-driver match-ups in the last 5 years, including a mad scramble in December 2024 when a client had 48 hours to ship 300 landscape lights for a resort opening. I've made the mistakes so you don't have to.

Here's a 4-step checklist I now use for every single fixture kit. It catches about 90% of the common mismatches before they become problems. Most installers skip at least one of these.

Step 1: Define the Total “Electrical Appetite” of the Kit

This sounds obvious, but you'd be surprised how often I see someone calculate based on one fixture and forget the other seven in the kit.

Grab a calculator (or your phone). For each fixture in the kit:

  • Find the Input Voltage (e.g., 12V AC/DC, 24V DC, or 120V AC line voltage).
  • Find the Power Draw in Watts (W) per fixture.
  • If you only see Amps (A), multiply Amps × Volts to get Watts. For example, a 0.5A fixture on a 12V line draws 6W.

Add up the total Watts for all fixtures, then add 20% headroom. So if your 8 floodlights each draw 15W (total 120W), you need a power supply rated for at least 144W. Round up to the next standard size. That's why the Mean Well LRS-150-24 (150W) is a popular choice for 24V kits in this range, or the LRS-200-24 (200W) if you want more room.

Heads up: I almost skipped this once on a small 4-light chandelier kit. Thought it was too trivial. But the specs were in amps, not watts, and I did the quick mental math wrong. The fixture arrived, it wouldn't dim properly until I swapped the driver. Power calculation wrong. Everything else irrelevant.

A Note on Voltage for 12V Kits

If your kit runs on 12V (common for small accent lights or some tree chandeliers), you'll likely need a Mean Well 12V 5A power supply (the LRS-100-12 or the enclosed LPC-60-12 series) if the total draw is around 60W. If you're powering something larger, like a sign, you might step up to the Mean Well LRS-150-12.

Step 2: Match the Voltage and Current (Crucial for LEDs)

This is the step where most “first time” mistakes happen. I see people buy a 24V power supply for a 12V floodlight and wonder why it's dead on arrival. Don't be that person.

What to check:

  • Constant Voltage (CV) vs. Constant Current (CC): Most generic lighting kits (especially floodlights and tape light) run on a constant voltage driver. The Mean Well LPC-60-700, for example, is a constant current driver often used for specific LED strips. Make sure the driver type matches the fixture's requirement.
  • Voltage Tolerance: The fixture will have a voltage rating (e.g., 12V DC, ±10%). Your power supply output must be within that range. Mean Well units are typically tightly regulated at 12V±2% for a CV supply.
  • If you're combining multiple fixtures in parallel: As long as the voltage matches, you can parallel them. The total current (Amps) will add up. Divide the total Watts by the Voltage to find the total Amps required.

For example, if your kit has 4 fixtures drawing 0.5A each at 12V (totaling 2A), you need a 12V power supply rated at least 2A. The Mean Well LRS-50-12 (50W, roughly 4.2A at 12V) is overkill in a good way.

Step 3: Verify Dimming Compatibility (If You Need It)

This is the one everyone forgets until they install it and the lights either hum or stay at full brightness. If the kit is for a dimmable application (like a chandelier in a dining room or adjustable floodlights in a conference room), you need to ensure the driver supports the dimming method your switch or control system uses.

Mean Well has a few approaches here:

  • 3-in-1 dimming (Resistor / PWM / 0-10V): This is common on the LPC-60-700 or HLG-120H-C1050A series. Check if your fixture is compatible with a 0-10V dimmer. If not, you might need a trailing-edge or leading-edge (Triac) dimmable driver.
  • Triac dimming: Some fixtures need a standard wall dimmer. Look for Mean Well models with a “D” suffix (e.g., LPC-60-700D) which indicates Dimming capability through phase-cut control.

I once had a client who bought a non-dimmable driver for a 10-fixture chandelier in a hotel lobby. The architect wanted it to dim for evening mood lighting. We had to swap all 10 drivers. Added three days and $400 to the job. The question no one asks is “will this actually dim the way my switch expects?” Ask that question before you buy.

Step 4: Check the Physical Fit and Location

You think you've picked the perfect electrical match. Then you go to install it and the power supply is too big for the electrical box. Or it doesn't have the right mounting holes for the chassis. Or the wire gauge is too thick for the terminal block.

What to check:

  • Form Factor: Mean Well has several series with different physical shapes.
    • LRS Series: Metal case, fanless, great for general-purpose and equipment racks. Usually around 215mm long for a 150W.
    • HDR Series: DIN rail style (like the HDR-60-24), perfect if you're mounting in a metal electrical panel with a DIN rail.
    • LPC Series: Slimmer, often IP67 rated for outdoor use (waterproof). The LPC-60-700 can be mounted on a chassis or in an enclosure.
  • Mounting Holes: Most LRS units have a standard 2-hole pattern. The HDR series clips onto the rail. Check before drilling.
  • Wire Connections: Mean Well uses high-quality, color-coded terminal blocks. If you're in a tight space, the top-entry vs. side-entry terminals matter.

Trust me on this one: I once tried to cram a bulkier LRS-200-24 into a shallow electrical box meant for a smaller switching supply. It literally didn't fit. I had to order a different model and pay $50 in rush shipping. If you're working with a shallow recessed electrical box, consider a smaller form factor like the LPC-35-700 or a DIN rail solution.

What Most People Get Wrong (And How to Avoid It)

The biggest myth I keep hearing: “If the voltage matches, any power supply will work.” That's about 80% true. The 20% that bites you is:

  • Ignoring the current rating: Over-driving an LED strip can fry it. Under-driving a floodlight can cause it to flicker or not reach full brightness.
  • Forgetting about startup current (inrush): A handful of large floodlights (especially with Mean Well drivers) can have a brief inrush current that trips a standard breaker if you have too many on one circuit. The datasheet usually states this under “Inrush Current.”
  • Not accounting for the environment: If the power supply is outdoors but not rated IP67, moisture can kill it. Mean Well has the “HLG” series for outdoor use, while the “LRS” is for indoor.

The question everyone asks is “What's the wattage?”. The question they should ask is “What's the full spec sheet, including dimming, form factor, and environment?” Do that, and you will not be the person making the “return-reorder-pay-rush-fees” phone call.

If I remember correctly, the pricing on the LRS-150-24 was around $30-35 as of early 2024, but that's just my recall from a project—don't quote me on current pricing. Check Mean Well's official website or your local distributor for current figures. The 3-in-1 dimming models (like the LPC-60-700) run a bit higher, maybe $40-50.

Bottom line: pick your Mean Well match using this 4-step list, and the only call you'll make is to tell the project manager it's done.