LED Work lights for milling machine

Hi Les, yes I meant that describing them as constant current devices (rather than neeeding a constant current) is lazy and inaccurate; it wasn't my clearest post though!

Neil

Hi Neil,
After making the comment about the the term constant current device I had a thought that I may have used the term in the way you used it in my previous posts. Other than that I think your post made it clear that some thought has to be given to driving LEDs from rectified AC (With or without a capacitor.) The peak current rating is not very much higher than the average rating. (Unlike quite a few semiconductor devices.) When white LEDs first became available I thought they would be good for a stroboscope but the low peak current rating made them less suitable. The 10 Watt arrays now available would probably work OK as even with a 1% duty cycle the average power would still be 0.1 W (Or a little higher using the peak rating.)

Les.

Latest installment.

Somewhere on page two Les made reference to those ring LED's called 'Angel lights'

Seen these used before where people clip them round the quill but they wouldn't suit me as i struggle sometime having the head hard up to a big dividing head doing splines.

When I looked though i found some 140mm ones, sounds big but they will just fit round the housing of a Bridgy head so clear of the dividing head.

Also saw somewhere on a forum where a guy had built a ring light and found out the tool was always in shadow, which makes a lot of sense but being big might get by this.

So sent for a couple.

Machined an alloy ring up with three steps in it, one to fit the casting, one for the ring light and one to retain the clear perspex cover to protect it.

Wire it up to a 15v wall wart at 400ma off an old power tool and this is taken at night with no other lighting on in the shop.

It does throw some shadow when the quill is down, virtually none when up. Can be easily removed by one screw and it does give a useful general light off.

With this and the earlier one with the two panels I can now dispense with the angle poise type lights which I hate with a vengeance.

Edited By John Stevenson on 29/05/2013 00:43:57

Bought a mains powered 10W LED worklight to replace the 500W incandesant one that I had been using. Plugged it in, and the RFI was terrible, I tried a ferrite ring on the power cord, no good, thought about taking it back, then tried a small isolating transformer, BINGO, no noise. Ian S C

Just received my two 48 LED panels from China.

Found a 12v-1 amp plug-in psu that used to provide the power for an old Netgear modem.

Hooked up the panels in parallel and they work a treat.

I have them on soak now in the kitchen, I'll give them a couple of hours to see how warm they get then look at ways of packaging them prior to attachment to the mill.

Len. P.

OO'ER this is all very laboratory speak. I think I'll stick to one of these - - - - - Rik

Rik,

Despite all the interesting experiments and speculation ... these 48 LED panels are designed as Car "Dome Lights" [Interior Lights], to be run from a 12volt Lead Acid Battery. They come with a range of adapters, to fit different Bulb Holders; or you can discard the adapter and just use the wires.

It really doesn't get much easier: Pretty much any nominally 12volt Battery will run one of these panels for a while.

MichaelG.