200W IP67 Waterproof LED Power Supply: Specs & Sizing

A 200W IP67 waterproof LED power supply does not deliver 200 W in a sign cabinet in July. It delivers about 140 W once the air around it reaches 60°C, which is what a sealed cabinet hits on a 35°C afternoon. If you size to the nameplate, you will be replacing drivers in month 30.

Here is what the 200 W class actually looks like and how to size it correctly.

What the R-200-xx Actually Is

Our 200 W IP67 unit (model R-200-xx) is a constant-voltage switching driver in a fully potted aluminium housing:

Derating: The Number That Changes Everything

Two corrections people forget. First, “ambient” means the air touching the housing, not the weather forecast — inside a sealed sign cabinet that is typically 20–25°C above outside air. Second, the 20% headroom rule exists for a reason beyond safety margin: switching drivers hit their best efficiency and their longest capacitor life between 60% and 80% load. Running a 200 W unit at 40 W is not “gentle” on it; it is mildly abusive.

So: if your real load is 160 W, a 200 W driver is the correct choice in a ventilated housing and the wrong choice in a sealed one. Go to 250 W.

12 V or 24 V: Decide by Distance, Not Habit

At 200 W, a 12 V output pushes 16.7 A; 24 V pushes 8.3 A. Power lost in the cable is I²R, so halving the current cuts voltage drop by a factor of four.

• Under 3 metres and under 50 W per run: 12 V is fine, and 12 V modules are marginally cheaper.
• 3–10 metres: 24 V. At 5 m on AWG 16 copper, a 12 V run drops roughly 1.8 V (15%); the same run at 24 V drops about 0.9 V (3.8%).

The cost of getting this wrong exceeds the cost of getting the wattage wrong. Oversizing by 50 W costs you a few dollars; picking the wrong voltage gives you a sign that is visibly dimmer at the far end, and the customer reads that as a quality defect. See 24V vs 12V Outdoor LED Power: The Voltage Drop Math for the formula.

How Many Signage Modules Will 200 W Run?

Work it backwards from the module. A typical injection-moulded signage module draws 0.72 W. At 160 W of usable load:

Leave the 20% headroom in there and you have a number you can defend. If your module count is above 250, split into two drivers rather than jumping to 350 W — two units mean one failure costs you half the sign, not all of it. Our load calculator worksheet walks through the full method.

Where 200 W Sits in the Range

• Below 120 W → 150 W is cheaper, smaller, and runs closer to its efficiency sweet spot.
• 120–180 W → 200 W, this page.
• 180–230 W → 250 W.
• Above 230 W in a sealed cabinet → 300 W.

If the housing is IP65 rather than IP67 — vertical facade, good drainage, no standing water — the CFX-200-xx IP65 unit is 153 × 80 × 32 mm and costs less. Our rainproof vs waterproof field data shows where that trade is safe.

Common Mis-Specifications

1. Sizing on nameplate watts. Cover the derating table first.
2. Ignoring inrush. Twenty drivers on one breaker can pull >60 A combined for a few milliseconds at switch-on. Stagger with a contactor or specify a soft-start.
3. Forgetting the drip loop. Cable routed upward into the gland feeds water straight in by capillary action. Route down, then up.

Get 200 W IP67 pricing — send wattage, voltage and quantity. Quote within 24 hours, MOQ 50 pcs, 15-day lead time. → Request a quote · Full IP67 buyer’s guide