Hi-Bay light spacing wisdom

[Flail]

Hi-Bay light spacing wisdom 42,250 Lumen Hykolity

I have a 20 W x 36 L by 20 H space that I want to put three high bay lights in. Does conventional wisdom space them at centerline of 9’, 18’ and 27’ or are the end light better closer to the ends or the centers to decrease shawdows and unevenness?

 

[CJseven]

I think more info would be needed on exactly which high bay fixtures your using.

 

[Flail]

These are 16” x 48’ type LED lamps with a 110 downward degree spread.

Regardless of the lamp style, given a limited number (3 in this case) of light sources, will lighting be more even with the end lights closer to the wall or just evenly spaced every quarter way down the ceiling? My thoughts are end lamps closer to the walls may be able to increase light reflection off the end walls and make lighting more diffuse. However, just evenly spacing the lamps may result in more even lighting. Any general rules to follow?

 

[kursplat]

it very much depends on what your doing at those ends. if i have a work bench at the end, and the light is going to be behind me all the time, i'm going to hate the shadowing and need another light over the work area. if i just have some shelves there that i don't use too often, no big deal. can you hang one or all three with cords so you can move them around until you like how they work?

 

[Radix2]

Obviously there is more light between two lights than there is between a light and a wall.

So normally you want the distance to the wall to be less than the distance between lights.

I'd do 6,18,30

 

[Platonic Solid]

With the limited info provided, I agree with Radix2. You will have shadows between walls and cars (assuming this is a 3 car garage used for wrenching). Supplementary fixtures will be needed if this is an issue for you.

 

[Flail]

So I put the lights up in a row down the middle of the 36’ run. They are spaced at 7’, 18’, 29’. The lights are 42250 lumens each for a total of 126,750 lumens. This equates to 9.25 lumens per cubic foot or 176 lumens per square foot. It’s nice and bright. Lighting seems very even. I work with machine tools and electronics. When I, get the heat going, I’m going to bring in a sandbox and work on my tan.

 

[Platonic Solid]

and link to fixtures used.

 

[Flail]

https://www.garagejournal.com/forum/attachment.php?attachmentid=827133&stc=1&d=1541632780

https://www.garagejournal.com/forum/attachment.php?attachmentid=827134&stc=1&d=1541632780

So using my harbor freight VOM which has a lux meter I get an average reading of 800 pointing up with peaks to 1200 pointed at the lights. Is this good?

I bought lights on Amazon: Hykolity 42250 lumens. Though these have a “cheap” name, I see the identical lights with different branding sold by “reputable” dealers on the net.

I chose these rather than 2 dozen Costco lamps as there is less wiring to pull 18’ up for 3 lights than 24.

Although the ceiling looks dark in the pictures, it really is like sunlight inside. I’m very happy with the brightness. I basically spent the same on these 3 lights as I would have on 24 lights but am days ahead on wiring.