johns purple beast
Member
Registered: 7th Nov 03
Location: herts
User status: Offline
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i brought sum leds off ebay i wire5 1 to the interier light it come on once n wont come on again does this mean it blew ??????? tried other 1 on side light done the same ???? plz help
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Adam-D
Member
Registered: 11th May 02
Location: Cheshire
User status: Offline
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yup i rekon its blew?
did they say thy were 12v ones ?
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johns purple beast
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Registered: 7th Nov 03
Location: herts
User status: Offline
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http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=2441941373&category=15329&rd=1 thats the 1s m8
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rollin
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Registered: 24th Apr 02
Location: Reading
User status: Offline
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id imagine it would have needed a resistor? so im guessing u blew it
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Houckham
Member
Registered: 29th May 03
Location: Newcastle upon Tyne
User status: Offline
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Alright lads
Ok your guess was right you need a "current limiting" resistor
This is because you only want 30mA at the most going throught your led.
(some are 20-28mA)
If your using 12V and you only want 1 LED in series.
Well you all know what comes next (GCSE Physics/Technology)
V=IxR rearranged to give R=V/I
(V= voltage, I= Current, R= resistance in Ohms)
you have about a 2.5V drop over the LED
that leaves 9.5V and desired 30mA - 0.03A
so 9.5/0.03 = 316.66Ohms
then your nearest resistor value is 330Ohm Resistor
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Houckham
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Registered: 29th May 03
Location: Newcastle upon Tyne
User status: Offline
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Heres a nice link
http://www.metku.net/index.html?sect=view&n=1&path=mods/ledcalc/index_eng#single
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James@CCC
Member
Registered: 10th Nov 03
Location: Eaton Bray, Bedfordshire
User status: Offline
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how well did u try it the second time? cos leds only work one way, so if u switch around the wires it might light up
maybe
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cobra148
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Registered: 27th Oct 01
Location: Here in front of my monitor.....
User status: Offline
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£3.50 each plus £1.50 postage
I can do a self flashing red or blue led in a nice chrome holder for a lot less than that, guaranteed to work too.
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whitter45
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Registered: 15th Nov 02
Location: Norton
User status: Offline
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J p B i recommnd u buy them off cobra as he knows what he is on about and always has top quality goods
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cobra148
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Registered: 27th Oct 01
Location: Here in front of my monitor.....
User status: Offline
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quote: Originally posted by whitter45
J p B i recommnd u buy them off cobra as he knows what he is on about and always has top quality goods
I'll have to put you on the payroll I think.
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OFcorsa
Member
Registered: 6th Jan 03
Location: Cheltenham, Gloucestershire
User status: Offline
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Cobra apologies for not sending you anything at the mo. i have been having my car mot serviced and repaired. £430 soi am skint however i ahve 5 pound coins your address and no envelope or stampso i will sort myself out shortly.
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bun
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Registered: 6th Oct 03
Location: Adel, West Yorkshire
User status: Offline
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cobra how much for however many l.e.d's i need to do dials plus m.f.d? corsa b by the way.
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whitter45
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Registered: 15th Nov 02
Location: Norton
User status: Offline
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Just trying to help u out cobra cos i feel bad about letting u down over the steering wheel. I will send my cheque off today for the leds
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cobra148
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Registered: 27th Oct 01
Location: Here in front of my monitor.....
User status: Offline
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OFcorsa, no probs mate, may I suggest though, if your sending me five £1 coins in an envelope, it might be safer to change it for a £5 note.
Bun, for £7.75 you can have enough plug and play leds to do the dials (with rev counter) and MFD in any colour you want.
Whitter45, don't worry about it at all, its no problem whatsoever. I appreciate the advertising
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OFcorsa
Member
Registered: 6th Jan 03
Location: Cheltenham, Gloucestershire
User status: Offline
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cobra - dont worry mate i was gonna do that, cos no doubt the posties willbe like ooh money in here errr lost int he post im afraid mate.
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