LED light help

[Rewind97]

Looking to replace my (12) 4 foot fluorescent lights with (12) 8 foot, 15,000 lumen LED’s in my 30’ X 40’ shop. Wondering if that is too much light. Should I go for (12) 4 foot 7,500 lumen lights instead? They will be 11’ off the floor. Both sets are 6,000K.

 

[kbuhagiar]

In my humble opinion, and based on my personal experience, you can NEVER have too much light...but...

If you are set on the 8-foot fixtures, make sure you use the ones that utilize 4ft tubes, as opposed to 8ft tubes, which are more expensive, offer less selection and are harder to handle & store.

Also, that 6000K light rating may be a bit harsh and tends to fall on the blu-ish end of the spectrum. Something closer to 4000K may be more appropriate.

Or not. YMMV.

 

[Bert_]

Are the fixtures you have decent? Line voltage retrofit tubes are a great option.

Guessing you are need more fixtures than what you have now

 

[danho]

I have 11 of the 8' fixtures in my 32'x40' shop, they are 14' off the floor and I would have no problem adding a few more. It is nice to have the light you need, when you need it. I also believe mine are in the 5500K spectrum which I prefer over the yellow end for shop work.

 

[Shiftless]

Looking to replace my (12) 4 foot fluorescent lights with (12) 8 foot, 15,000 lumen LED’s in my 30’ X 40’ shop.

Guessing you are need more fixtures than what you have now

More fixtures would give you more even lighting and fewer shadows. For comparison, in my tiny 20x20 garage I have 9 twin tube 4 foot long LED tube fixtures. I like my 4000K color temperature.

 

[cybrdyke]

Looking to replace my (12) 4 foot fluorescent lights with (12) 8 foot, 15,000 lumen LED’s in my 30’ X 40’ shop. Wondering if that is too much light. Should I go for (12) 4 foot 7,500 lumen lights instead? They will be 11’ off the floor. Both sets are 6,000K.

Your existing lights are delivering about 3500 to 4000 lumens each. You will be nearly quadrupling the amount of light. 15,000 lumens at 11' is likely to be pretty harsh. 6000K is annoyingly blue. It's also a red flag that the manufacturer is using factory seconds when it comes to diodes.
All that said, you're approaching this wrong. The proper way is to determine how much light you need (in foot-candles) and then choose the fixtures that will get you to that target. There are so many variables in each shop that it's virtually impossible for anyone to determine how many fixtures you'll need.
But, if you dont want to go through that, then just figure that you've currently got about 4000 lumens per fixture and go from there.
Good luck,
CD

 

[Rewind97]

In my humble opinion, and based on my personal experience, you can NEVER have too much light...but...

If you are set on the 8-foot fixtures, make sure you use the ones that utilize 4ft tubes, as opposed to 8ft tubes, which are more expensive, offer less selection and are harder to handle & store.

Also, that 6000K light rating may be a bit harsh and tends to fall on the blu-ish end of the spectrum. Something closer to 4000K may be more appropriate.

Or not. YMMV.

After looking, I think you’re right, 6K might not be right for me, probably drop down to 5K

 

[Rewind97]

Your existing lights are delivering about 3500 to 4000 lumens each. You will be nearly quadrupling the amount of light. 15,000 lumens at 11' is likely to be pretty harsh. 6000K is annoyingly blue. It's also a red flag that the manufacturer is using factory seconds when it comes to diodes.
All that said, you're approaching this wrong. The proper way is to determine how much light you need (in foot-candles) and then choose the fixtures that will get you to that target. There are so many variables in each shop that it's virtually impossible for anyone to determine how many fixtures you'll need.
But, if you dont want to go through that, then just figure that you've currently got about 4000 lumens per fixture and go from there.
Good luck,
CD

After looking online it seems about 90K lumens (total)is what is suggested for my size shop. The 8 foot tubes would be twice that. With the 4 footers I’m worried about shadows.

 

[pbon]

In 800 SF, with 9.5’ ceilings, I have 18 LED strip lights that are 4’ and 5000k and 5000 lumens and have diffuser lenses. The shop is 24x30 but has a lower ceiling 15x6 bump out along part of the length on one side, a recess in the ceiling above the lift on one side, a beam halfway across the width, 2 sets of garage door tracks, and a set of stairs along one side length. Those obstacles make it hard to do an ideal layout for efficiency.

I like the result, but have never done any scientific measuring to see the foot candles where I work, which can be anywhere. I did install the lights with 4 zones or switches, each with a dimmer, but rarely use the dimmers unless I am just hanging out socializing in one corner of the shop.

 

[cybrdyke]

After looking online it seems about 90K lumens (total)is what is suggested for my size shop. The 8 foot tubes would be twice that. With the 4 footers I’m worried about shadows.

If you saw something online that mentioned "total lumens", then you should immediately know that they have ZERO credibility and shouldn't listen to anything they say. They are idiots.
If you're worried about shadows, get a lighting layout done, or find a similar sized space in the "LIGHTING LAYOUT" thread.
4' vs 8' shouldn't be a concern.
It's just that 8' fixtures are a PITA.
CD

 

[Bert_]

If you saw something online that mentioned "total lumens", then you should immediately know that they have ZERO credibility and shouldn't listen to anything they say. They are idiots.
If you're worried about shadows, get a lighting layout done, or find a similar sized space in the "LIGHTING LAYOUT" thread.
4' vs 8' shouldn't be a concern.
It's just that 8' fixtures are a PITA.
CD

100%. Total lumens isn't a meaningful figure.

I like 8' fixtures. 4' fixtures take more time because you usually need 2x as many!

 

[cybrdyke]

I like 8' fixtures. 4' fixtures take more time because you usually need 2x as many!

How true!
When I say PITA, its more about shipping and handling and moving them around a job site. Once on the ceiling, they're pretty nice.
CD

 

[PWC Repair]

My 2 cents. I've had led lighting in my shop for 6+ years. Ballasts started failing and I'm currently switching the fixtures out as I find time. 4500k-5500k is the sweet spot. Anything above that contains too much blue light and is actually not great for your eyeballs. Below that it becomes too yellow and will remind you of some old guys den.......you know, with wood paneling and those magazine holder lamps! GET DIFFUSERS of some sort. A clear lens on a bright led shop light just causes TOO MUCH glare! My new lights don't have diffusers but they have frosted lenses that curve up the sides of the housing a bit. I like them MUCH better than the old lights cause they throw the light out much more evenly. Maybe a thought for an 11ft mounting height, mine are at 13.5ft. I have 8 in a 30x48x12 shop.

https://www.amazon.com/Lightdot-Illumination-Eqv-600W-Warehouse-Energy-Saving/dp/B0BS6RJ3JN/?tag=atomicindus08-20

 

[Rubicon914]

I’d consider using some UFO lights. You can get 5000k 150 watt plug in fixtures that put out 21,000 lumens at each fixture, with or without 0-10v dimmers at very reasonable prices. Just one unit will easily blow away the performance of a row of old school fluorescent fixtures, even with new LED bulbs in them. For a shop your size I’d get 10-12 lights so you can get 60-70 foot candles per square foot and eliminate all shadows. Seriously, I’d order just one UFO light for now and hang it up. It will make you change your mind about fluorescent fixtures. I was like you, and was going to install 4’ fixtures all over my 20X30 3 car garage (10’ ceilings) but I’ve been testing out just TWO UFO lights and they are a total game changer. I literally have hospital lighting in my garage and the light is not yellow or blue - just natural 5000K white light. Just be warned, don’t look up directly at the UFO lights unless you have dimmers on them.

 

[dave*99]

Your existing lights are delivering about 3500 to 4000 lumens each. You will be nearly quadrupling the amount of light. 15,000 lumens at 11' is likely to be pretty harsh.

I’d consider using some UFO lights. You can get 5000k 150 watt plug in fixtures that put out 21,000 lumens at each fixture, with or without 0-10v dimmers at very reasonable prices. Just one unit will easily blow away the performance of a row of old school fluorescent fixtures, even with new LED bulbs in them. For a shop your size I’d get 10-12 lights so you can get 60-70 foot candles per square foot and eliminate all shadows.

Sounds like heading in the wrong direction. If 15000 is harsh, 21,000 will be worse.

Foot candles per square foot is not a real measurement. One foot candle is equal to one lumen per square foot. 50 to 100 foot candles at the work plane is a good level for most shops. Task lighting can be added at machinery if needed.

I was able to use a smart phone app to measure light at my work plane. I measured the light on top of my table saw in my old shop. It was 50fc. So I designed my new shop for 50fc. I used a lighting calculator from the lighting manufacturer. The new shop landed at 53fc on the table saw. Perfect.

The OP has 11' high lighting. I'd be looking for frosted tubes (diffused light.)

 

[AC-WC]

I have 75,000 lumens in my 22X27 garage with white cathedral ceiling. Color is 5k and everything is just right. That's twelve 4 footers arching the ceiling and two over my bench and 1 at the walk-in door. Not sure I would like 6k color.