Fluorescent or LED tubes

[RichD1]

Just about to go out and buy 4 x twin 58w HF fluorescent fittings to light my workshop. I came to this conclusion as I found a website which told you how to work out light levels. They recommended 200 lumens per square feet for bench work and with my workshop being 156 sq ft comes to around 30,000 lumens. A 58w tube is rated at 5200 lumens, so I needed 6 tubes. Decided on 8 tubes just to be on the safe side.

I've been made aware that you can get LED replacement tubes so did some web searches and discovered that a 5ft LED produces around 2200 lumens but as the light is all directed down rather than spread all around you don't need as many lumens to get the same level of light from an LED tube. One website suggested that you only need 1/3rd of the light output to compare with a conventional tube.

Has anyone had any experience of LED tubes and the light levels that they produce and can I reduce the number of tubes I need to fit?

Richard

 

[viewer]

Apologies for not answering your question, but have suggestions for checking the requirements.
Is the workshop only 156 square feet (i.e. 10' by 15' - single garage)?
Do you need the whole area at the same illumination or just the work benches? If the benches, how big and where placed?
200 lumens per square foot would be fine for very detailed work, but not needed for the whole room, indeed may be a nuisance.
How high is the ceiling and how do you avoid shadows (the two go together of course)?
Does the colour temperature matter to you?

 

[RichD1]

Workshop is 5m x 3m and is in the empty state at the moment, getting ready to plan out the layout. ceiling height is only 2.2m. The workshop has natural light at one end through french doors and 2 side windows. The bench area will probably be at this end.

I'm looking for good general lighting, but was thinking of having the individual units or pairs of units switchable so that I can vary the lighting level.

The current plan was to have 2 rows of 2 x twin 5ft fittings down the 5m length.

I was assuming that I would have ordinary daylight tubes. Is this correct?

It was when I was working out the power required for my wiring that I realised that each twin fitting would pull around 150W, a bit less if using high efficiency units. That makes around 600W!!

When I looked at LEDs the 5ft tubes are rated at 20w to 25w each. If they are right in that they only need 1/3rd of the output of a fluorescent, then I won't need so many tubes.

Also just found a forum thread that calculated that I only need 15000 lumens, or 4 single 5ft fluorescent tubes.

So I'm a bit confused now.

Richard

 

[knowall]

If the workshop is unpainted brick or timber i.e. dark surface it will guzzle the light.

Paint the walls a ceiling a light colour and you can reduce the number of fittings.



KA

 

[flameport]

4 twin fittings will be ridiculously bright.

For a garage of that size, 2 single 58W tubes will be plenty. If the ceiling was higher and the walls/ceiling painted white, a single tube would be adequate.
If you want additional lighting for certain tasks on a bench, fit an additional light to that bench only.

As for colour, get whatever you want.
My choice would be Activa172 tubes, but you might not like those.

 

[Iggifer]

I would not go for LED fluorescent tubes yet, all of the ones I have seen (including Philips) are a bit rubbish.

For starters, the LED's are only on one side of the tube, so instead of having 360deg light, and bounce back from the fitting, you get ~180deg of light, and it means lots of dull areas.

With flurry tubes, paint the walls and ceiling white, job done

 

[knowall]

I would recomend triphosphor tubes for workshop use.

KA

 

[RichD1]

Only 2 x 58w fittings!!! I have 5 x 58w and 1 x 40w fittings in my garage which is 5.5m x 4.5m and this only gives a general background level and certainly not enough for close work at a bench or using a woodworking machine.

BTW the workshop is newly built and will have light coloured walls floor and ceiling. The ceiling will probably be white.

LEDs having 180 degree light is ideal isn't it. That means it covers everything from where it's mounted to the floor. This is why they say that you don't need so many lumens as everything is direct downward rather that shattered upwards and wasted.

My local Electrical Wholesaler have some LED tubes in their showroom so will go over and have a look.

Richard

 

[big-all]

you are talking 23 x100w equivalent bulbs in the that calculation 1300x40=30000
i would suggest 25%off that would be fine or 7000-7500 lumens

i have a 4w 2 x7w and 1x10w leds in my 10x12ft workshop equivalent to 2500lumens
the maximum i would need to give high levels would be 5x10w or 4300lum

 

[Iggifer]

LEDs having 180 degree light is ideal isn't it. That means it covers everything from where it's mounted to the floor. This is why they say that you don't need so many lumens as everything is direct downward rather that shattered upwards and wasted.

You would think, but believe me, LED 58w equivalent tubes are not as bright as 58w tubes. For the time being I would go fluorescent over LED any day of the week

 

[RichD1]

I found the formula for lumens on various web site forums but they do contradict each other.

As I said one formula worked it out at 31000 lumens another (which I think is on this site) suggested 15000 lumens.

Reading the American woodworking forums, they seem to work on 2 watts to 3 watts of light per square foot. So that would make about 350 to 450 watts of lighting.

Still think I will fit twin fittings and then try and wire each tube individually so I can vary the lighting requirements depending on the activity.

My original question was whether it was worth investing in LED tubes, apart from Iggifer I've not had any other advice.

Richard

 

[big-all]

when you can get a 10w[90w equivillent ]for £6 those tubes look expensive

i have 3x4ft tubes in my workshop but dont use them and wouldnt swap to led tubes at those prices
at the min i am using clip on and plug in lamps as i can move the lamps as required to stop shadows
http://www.amazon.co.uk/CLIP-ON-LIG...&qid=1386713724&sr=8-4&keywords=clip+on+lamps

 

[RichD1]

Thanks Guys,

Will stick with conventional fluorescents for now then.

So I'm going for HF units 4 x twin 58w in the protective case. As I said I'm hoping that I can re-wire the fittings to allow me to have one or two tubes on as required.

I'll let you know how it works out when I get them fitted which hopefully will be in the next few weeks.

Richard

 

[FDJ]

4 twin fittings will be ridiculously bright.

You can never have too much light in a Workshop.


Frank

 

[big-all]

4 twin fittings will be ridiculously bright.

You can never have too much light in a Workshop.


Frank

i have 3x4ft tubes in my 12x10ft workshop 1is enough most off the time a second one to stop shadows but never 3 as its to bright
much better to have slightly 2 much than not enough but 8 tubes ??? 4 or 5 would be more than enough in my opinion