Replacing Metal Halide with LED: Wattage Equivalents That Actually Work

Somebody points at a 400 watt metal halide and asks what LED replaces it. The honest answer is that wattage is the wrong unit for the question. Lumens are the right one, and the lamp maker's data sheet gives you the number to match. This guide shows the lamp figures, the lumen check, LED area lights we list at each output, and the two things that draw complaints after the swap.

Why wattage comparisons mislead

Watts measure what a fixture consumes. Lumens measure what it produces. A metal halide lamp and an LED fixture turn watts into lumens at different rates, so a wattage equivalence is really a lumen comparison wearing a wattage costume.

Two things make the gap wider than it looks.

Initial lumens versus mean lumens

A metal halide lamp is brightest when new and falls from there. A lamp maker's data sheet for a standard 400W probe start lamp lists 36,000 initial lumens and 23,500 mean lumens, burned vertically. The number on the lamp box is initial. The light in the building after the lamp has run a while is closer to mean.

LED fixtures state lumen maintenance as an L70 rating, the hours until output falls to 70 lumens per 100 it started with. The EDIPAI G8 area light sheet, for example, lists L70 at 50,000 hours or more.

Where the light goes

A metal halide lamp sends light out in a full circle around the arc tube, and the fixture's reflector has to turn it toward the ground, losing some along the way. An LED fixture's lumen rating is measured for the whole fixture, so it already counts what leaves the lens.

The lamp figures

These are clear standard probe start metal halide lamps, universal burn position, from lamp makers' published data. The planning target is the lamp's mean lumens. The 400W mean figure comes from the data sheet; the others apply the same mean to initial ratio as the 400W lamp, about two thirds, so treat them as estimates.

Pulse start lamps run higher. One 400W pulse start data sheet lists 42,000 initial and 29,400 mean lumens, so check which lamp is in the fixture before you size the LED. For high pressure sodium, use that lamp's own data sheet the same way.

Check it with the lumen math

If you can find the old lamp's data sheet, the check is quick.

Because lamp lumens are measured bare, before the reflector and lens, matching the lamp's mean lumens with the LED fixture's rated lumens is a conservative target. The old shorthand of dividing metal halide wattage by three puts a 400W lamp at about 133W; the lumen check is the better guide because LED efficacy varies from one fixture to the next. For a finer answer, run a layout from the fixture's photometric file.

LED area lights we list, by output

Parking lot shoeboxes are a common metal halide swap. Lumens below are the maximum on each manufacturer's spec sheet; the selectable wattage heads can be set lower on site.

Check each product page and spec sheet for that fixture's UL, ETL and DLC listings. Browse more in our area lights collection, and see our parking lot lighting guide for distribution and pole spacing.

LED high bays we list for 400W warehouse swaps

Inside a warehouse the 400W lamp usually hangs in a high bay. The same lumen check applies: aim for 23,500 lm or more. Lumens below are the maximum on each product listing.

See every option in our high bays collection.

Two things that generate complaints

The color shift

High pressure sodium light is orange, and metal halide lamps can shift in color as they age. A 5000K LED looks different from either, so if nobody warned the owner, the first reaction can be that it looks cold rather than correct.

Say it up front, and where the space is customer facing, consider 4000K instead of 5000K. The JEE AR08 and AR09 sheets list 3000K, 4000K and 5000K selectable on one head, so you can set one fixture, look at it, and then set the rest. More on field selectable fixtures and in our LED color temperature guide.

Glare

Metal halide in an old reflector is diffuse and somewhat forgiving. An LED array is a small, bright source. At low mounting heights, or where people look up, that reads as glare even when the foot candle level is correct. Look for a diffused lens or a higher mounting position rather than more output.

What changes after the swap

• Lamp changes: the lamp data above lists rated life of 10,000 to 20,000 hours, and in a high bay or on a pole each change means a lift. LED fixtures state an L70 rating instead.
• Restarts: the 400W lamp data sheet lists a warm up of 3 to 5 minutes and a hot restrike of 5 to 10 minutes. An LED fixture has no restrike wait after a power blip.
• Energy: to work out the cost and payback for your hours, use our LED retrofit payback guide.
• Incentives: if DLC is new to you, read DLC listed LED lighting explained, and see our utility rebate overview for what to keep from the job.

Where each replacement lives

Common questions

What LED replaces a 400W metal halide?

Match lumens, not watts. A lamp maker's data sheet for a standard 400W probe start lamp lists 23,500 mean lumens, so look for an LED fixture rated at 23,500 lm or more, such as the JEE AR09 100 to 150W at up to 25,500 lm.

What LED high bay replaces a 400W metal halide high bay?

Use the same lumen check: 23,500 lm or more. The JEE LHB10 2ft linear high bay is listed at up to 25,600 lm at 160W, and the JEE LHB09 180 to 220W at up to 30,800 lm.

What is the difference between initial and mean lumens?

Initial lumens are the lamp's output when new. Mean lumens are its output after it has run a while, and they are lower. For the 400W probe start lamp above, the data sheet lists 36,000 initial and 23,500 mean.

Does the divide by three rule still work?

It puts a 400W lamp at about 133W, but LED efficacy varies by fixture. Comparing the lamp's mean lumens to the LED fixture's rated lumens is the better check.

What LED replaces a 1000W metal halide?

A standard 1000W probe start lamp lists 110,000 initial lumens. Using the same mean to initial ratio as the 400W lamp gives an estimate of about 71,800 lm, and the JEE AR09 300 to 500W is rated up to 80,000 lm.

Will the LED look different from the old lights?

Yes. High pressure sodium is orange and metal halide can shift in color with age. Consider 4000K for customer facing spaces, and set one selectable head before the rest.

Replacing more than a few fixtures? Send the existing count, the mounting height and the lamp wattage for a job quote. Questions? Contact us or call 845-681-2684.