I am rubbish at electrickery

[fatblokish]

In fact, having inherited an knackered old lawnmower, I once set about cannibalising the orange flex to use as an extension lead. I cut off the old weird shaped plug that slotted into the mower itself and replaced this with a conventional plug. A rather painful electric shock then followed before the realisation dawned that instead of a replacement plug, I should have used a replacement socket.

Anyway, I want to wire up a 240v flashing LED light. The LED bulb itself should be the sort that is often found to indicate that equipment is charging, 3mm diameter? And red.

Can this be bought in Maplins, and if so, what do I need.

BTW, I absolve anyone replying to this thread any liability for my own incompetence.

ta

 

[subaqua]

Step away from the tools .

Why do you want a flashing LED and where , these are the 2 things to be bottomed out before we can proceed with a safe answer.

The avatar should give you a clue to my job !

 

[Drago]

Oh dear...

 

[fatblokish]

Never stuck a knife in the toaster though, that would be plain stooopid.

The LED would be wired up into my shed, to replace a battery powered flashing LED whose AA's die after a week or so, and mimics an alarm system. This would be visible only to those ne'er'do'wells already in the garden and poking about. The shed is presently wired up for mains.

I would use cable clips to hold the new cable in place and the LED would shine through a 2mm ish diameter peep hole, so fixed in place and weather protected.

Your thoughts on the components required?

 

[Andy_R]

240Vac - 5Vdc mains stepdown transformer, something like 2.7 ohm resistor and 3.3V Led in series. But maybe not.

 

[deptfordmarmoset]

My experience of chemistry (and physics) involved an attempt to light a filched strip of magnesium in an electric fire. It hurt. At least I now know that magnesium conducts electricity. In the grand scheme of things this post doesn't help much apart from disqualifying me from ever giving advice on either subject.

 

[fatblokish]

You should have used a pair of them chemistry lab metal tongs

 

[Spinney]

My experience of chemistry (and physics) involved an attempt to light a filched strip of magnesium in an electric fire. It hurt. At least I now know that magnesium conducts electricity. In the grand scheme of things this post doesn't help much apart from disqualifying me from ever giving advice on either subject.

You are one of the reasons that any magnesium ribbon to be used in chemistry lessons stayed in my labcoat pocket and was doled out one strip at a time - the roll was not left on the bench for pupils to get what they needed!

 

[deptfordmarmoset]

You are one of the reasons that any magnesium ribbon to be used in chemistry lessons stayed in my labcoat pocket and was doled out one strip at a time - the roll was not left on the bench for pupils to get what they needed!

Sorry Miss. (I must add I've learnt a lot since then, including the knowledge that I'm too soft headed for hard sciences.)

 

[young Ed]

now i'm no expert on leccy but i would be thinking along the lines of a transformer stepping it down from 240v to 5v DC and then either if you can get a flashing LED module simply wire it up pos to pos and neg to neg
although easiest way i would consider is wiring up your current flasher unit via a transformer, what batteries and how many does it use?
Cheers Ed

 

[Andy_R]

You are one of the reasons that any magnesium ribbon to be used in chemistry lessons stayed in my labcoat pocket and was doled out one strip at a time - the roll was not left on the bench for pupils to get what they needed!

oooh....oooh...me, miss....we had a chemistry teacher who tried to show us what happened when you add blood to hydrogen peroxide...nothing. It should have gone fizzfizzfizz, but he'd had a "liquid"lunch so the alcohol in his blood had a retardant effect - he even said so. This was the 1970's, so think "Kes" type teachers

 

[voyager]

try a 12v main psu -
http://www.ebay.co.uk/itm/55034-AC-...982731?hash=item3f4515980b:g:4vYAAOSwLVZVis8l

and
http://www.ebay.co.uk/itm/like/1213...ICEP3.0.0-L&ff14=122&viphx=1&ops=true&ff13=80

then you have a 50/50 chance of getting the connector around the wrong way BUT you ( famous last words ) won't electrocute yourself

regards emma

 

[young Ed]

http://www.ebay.co.uk/itm/2x-LM358-...049088?hash=item5d5d866c00:g:uOYAAOSwuMFUftrQ
that might do the job?
Cheers Ed

 

[voyager]

http://www.ebay.co.uk/itm/2x-LM358-...049088?hash=item5d5d866c00:g:uOYAAOSwuMFUftrQ
that might do the job?
Cheers Ed

Chinese and 8 white light leds , still an interesting find young Ed

 

[subaqua]

how much is it to replace a battery every couple of weeks ?

versus

cost of materials , cost of keeping a transformer energised constantly ?

about 1000 hours from a battery in a flashing unit.

however if you wish to


please do not use croc clips like this !

you will need to be adept with a soldering iron and some veroboard


and as for sticking knives in toasters, i am not saying anything ................