Thread: Workshop Led Strip Lighting.

Ray, just a thought - should this thread be moved to "The Shed"?

Originally Posted by Zaphod

Here is what you need for good space lighting:12W 3500K 800LM Warm White LED Emitter Metal Strip (12~14V) - Free Shipping - DealExtreme They're warm white, but MUST be mounted on some aluminium (steel would be OK - use silicone adhesive) for heat sinking and MUST be used with either a current source or a limiting resistor. As for Lumen outputs, the general rule-of-thumb is that standard IC (Incadescent) is around 5 ~ 15 Lumens/Watt, Halogens are around 20 ~ 25 Lumens/Watt and high quality LEDs run from around 80 ~ 130 Lumens/Watt.

They look quite interesting Trevor, and only 120mm long too.

Some questions:
Just reading one of the reviews, it looks like they are dimmable?
Can they be wired up in parallel (I'm wondering if that would reduce the amount of wiring because the long roll that Ray is considering appears to only need a couple of wires)
Would you be able to take a photograph of a situation please? (but making sure that the camera is set to "Daylight", as this will give a reasonable indication of the warmth, but if the camera is set to "Auto-light balance" it will self-correct the colour to daylight, more or less).

Originally Posted by RayG

There is a heap of 188 watt solar panels on Gray's at the moment, but it's pickup only in Tasmania...

Bugger. Auction ends the day after I leave for the great north island. Otherwise I could have brought a truckload over with me.

If you're serious about having a crack at them send me a PM, something might be possible..... I'm sure I can arrange for pickup anyway. What are friends for if not to exploit.

PDW

[QUOTE=FenceFurniture;1654971]They look quite interesting Trevor, and only 120mm long too.

Some questions:

Just reading one of the reviews, it looks like they are dimmable?

Yes and, no. Since they are 'raw' LEDs, they must be used with a constant current source. Unlike IC lamps, the CURRENT must be altered, not the Voltage. This is slightly more difficult than arranging for a variable Voltage source. Don't forget: Even though they are compact, they should be securely mounted to a material that can remove some heat (a piece of, say, 150mm X 50mm X 3mm aluminium should work fine).

Can they be wired up in parallel (I'm wondering if that would reduce the amount of wiring because the long roll that Ray is considering appears to only need a couple of wires)

Again, yes and, no. Each LED would require it's own current source (or resistor). Then they can be paralleled. They can, of course be operated in series.

Would you be able to take a photograph of a situation please? (but making sure that the camera is set to "Daylight", as this will give a reasonable indication of the warmth, but if the camera is set to "Auto-light balance" it will self-correct the colour to daylight, more or less).

Will do. Sorry for the messy editing. For some reason my I cannot insert line breaks.

Just a quick update,

The led strips arrived, ... and last night I got a chance to have a play with them... not impressed.. the 6500K light is a sickly bluish colour and the light output is much less intense than a fluoro tube, total lumens is probably as per spec, but 800 lumens per meter versus 3000 lumens per meter is quite noticable.... you might get similar lux by running the strips back and forward 4 or 5 times... but I don't like the colour, so I'm waiting now on the 100W floodlights to arrive before moving onto the next stage.

These weren't my first choice, a little more expensive than I'd like, and will need to be modified for low voltage operation. The high powered led arrays are usually 30V or so, and that might mean the solar panels/ batteries will need to be 48V, either that or a boost smps will be needed. Not sure...

100W Outdoor LED Tunnel IP65 Floodlight White High Power Spot Flood Lights AU | eBay

These are supposed to be 2800~3200K Warm White.

Regards
Ray

Originally Posted by RayG

These are supposed to be 2800~3200K Warm White.

That will be much nicer. The Aldis globes I installed are 3000* and are pretty much spot on for "pleasant colour".

Just looking at those floodies - I think they are going to throw a pretty sharp shadow (sharp-ish penumbra), and I reckon that will be pretty annoying - throwing your own shadow onto your work. Sorry about that....

EDIT: Many years ago, i had a floodlight in my office, but it was pointed up at the white ceiling, in the same way that a photographer uses "bounce" flash. This was spectacularly nice light to work under - virtually shadowless. But it comes at a power consumption price.

Hi Brett,

I think you're right about the shadows with no diffuser..

The shed ceiling is insulated and painted white, so I can bounce off the ceiling, I'm interested looking further at the Cree CXA series, Cree XLamp CXA3050 LED Array

They claim to be getting 10,000 lumens ... that's worth 3x fluorescent tubes.

Regards
Ray

The problem with bouncing is that you'll need about 50% more lumens to get the same lux (as a guestimate). You can probly work out the % loss by measuring any old flood light at a given distance, and the bouncing it off said ceiling. That will tell you the % loss for the paricular ceiling (not specifically the light source). Even measuring a camera flash under the two conditions will tell you.

If you solar panels can produce enough grunt to cover the loss then you'll be okay ('cept you'll have to buy more higher powered lights a $more).

I don't think a diffuser over the floodie will be the best solution - it will disperse the light wider (and of course with more dropoff according to the inverse square law), but it won't soften the shadows enough, I don't believe.

EDIT: The only way that a diffuser will soften the shadows enough is to put distance between the floodie and the diffuser - the softer shadows are a result of the area of the light source itself (which id the diffuser in this case).

Forgive me if I'm telling you stuff that you are well and truly aware of.

Led lighting

The 100 Watt led floodlights arrived today and I've done a few tests to see what the "warm white" colour temperature looks like, its a pleasant warm bright colour, I'd have no problems with, unlike the sickly blue of the 6500K led strips... So colour is good..

I haven't yet pulled one apart to see what mods might be required for battery operation, but here are a few pics of the LED floodlight, note the large heatsink!...

DSCN3077.JPGDSCN3078.JPGDSCN3080.JPG


Lux readings on the Hioki Lux Meter were around the 450-500 lux for directly under the fluoroescent fittings, and around 3000 lux for the LED floods, dropping to 1500 Lux with bouncing off the white painted roof.

The best lit workshop I have is the wife's quilt workshop which has 12 double fluoroescent tubes ( 24 total ) in a 6m x 6m workspace, average lux is around 1000, or, approx 1/3 of the light intensity I'm getting from the one 100W LED flood...

So, that solves the lighting problem, now to figure out out how to make it solar powered .....

Regards
Ray

hi Ray

looks good some pics please set your camera to manual so we can see a direct comparison from fluro to led
we bounce fluros off the roof at work it the areas that have computers doing colour critical jobs its a nice flat even light our fluros are 6500k as this is the standard daylight colour for photographic colour critical applications the strip lights I recon are closer to 7500k from my experience

you should be able to save some power in the quilt room (12 double fluros you must have shares in the power company's )

cheers
Harty

Just remember Ray, Ground wire:Yellow one

Your thumbnail pic of Josh's backside won't enlarge either for some reason. (i see its gone now)

They look good, but still only 100lm/W, not groundbreaking efficiency, there seems to be a line at 100Lm/W that is hard to beat.

FWIW in my 66m i have 8 double fluro's, i find with task lighting its fine.

Hi Ray,
Have you measured the input power as yet?
I see so many W numbers but rarely the input. I assume with something like that light if the LED is 10W there wont be to much power going into driving it. some of the other LEDs that just use resistors make me wonder.

Stuart

Hi Harty,

Easier said than done, here are some pictures with the LED flood (bounced off the roof) and fluoro's

DSCN3082.JPGDSCN3083.JPG

DSCN3084.JPGDSCN3085.JPG

I can't see the difference in the pictures that I can see in real life..

Not sure how to photograph the difference, the camera seems to be compensating somehow


Regards
Ray

Hi Ray, are the top two pics both of the LED source, or one LED, 1 fluoro?