resistance of bulb
resistance of bulb
quick question - anyone got a rear light bulb 12v21/5W hanging around and a multimeter? could you measure the resistance through each filament for me and let me know what it is.
Thanks
SKidMark
Thanks
SKidMark
AR's rock!!!
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.
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fallenmikethebike
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Re: resistance of bulb
Not my field of expertise, but, I have a reading of , less than .2 of an OHM on one, and virtually zero on the other.
I cleaned the terminals before measuring.
I don't have a spare holder to test which is which though.
Mike
I cleaned the terminals before measuring.
I don't have a spare holder to test which is which though.
Mike
VFORCE REEDS-MUGEN HEAD AND BARREL-WHITE POWER-ALL ON MY WISH LIST!!
Re: resistance of bulb
I don't have a lamp in front of me to measure, but should be able to work it out with basic forumlae.
P = IV, so I = P/V = 21/12 = 1.75A for 21W filament.
and 5/12 = 0.417A for 5W filament.
Then, V = IR, so R = V/I = 12/1.75 = 6.86 ohm for 21W filament
and 12/0.417 = 28.78 ohm for 5W filament.
Hope that helps
P = IV, so I = P/V = 21/12 = 1.75A for 21W filament.
and 5/12 = 0.417A for 5W filament.
Then, V = IR, so R = V/I = 12/1.75 = 6.86 ohm for 21W filament
and 12/0.417 = 28.78 ohm for 5W filament.
Hope that helps
Re: resistance of bulb
thanks for your reply guys. Hallsy I already calculated that but I used R-E2P as they were the values I had... 
Anyway the calculated values and measured values don't tie up as Mike's figures showed. The reason for all this was to figure out which wire at the Tail/Brake light was for each. I know that the green is GND but could someone tell me which of the brown and green/yellow are for the tail light and which is for the brake light.
Cheers SkidMark
Anyway the calculated values and measured values don't tie up as Mike's figures showed. The reason for all this was to figure out which wire at the Tail/Brake light was for each. I know that the green is GND but could someone tell me which of the brown and green/yellow are for the tail light and which is for the brake light.
Cheers SkidMarkAR's rock!!!
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.
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knackeredMk1
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Re: resistance of bulb
I take the capacitor out of the wiring system (the one near the headstock) and replace it with a lower voltage battery (I use a PP9 (9v)). This way I can test all the wiring and switches.
You could use a much lower voltage if you think that 9v would damage the electronics I suppose but this is the way I've always done it without problems. Can't get much current to do damage due to the internal resistance of such a small battery
.
But ARs are such finicky creatures ...........
You could use a much lower voltage if you think that 9v would damage the electronics I suppose but this is the way I've always done it without problems. Can't get much current to do damage due to the internal resistance of such a small battery
.But ARs are such finicky creatures ...........
Re: resistance of bulb
thanks but just tried that doesn't seem to work on a AR - I got the neutral light on but nothing else... 
AR's rock!!!
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.
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knackeredMk1
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Re: resistance of bulb
Check the colour of the wires coming out of the brake light switch .
.Re: resistance of bulb
THANK YOU - black and green/yellow so I can take it that the green/yellow is the feed for the brake light!knackeredMk1 wrote:Check the colour of the wires coming out of the brake light switch
AR's rock!!!
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.
TwinAir filter, Braided Brake Hoses, Swingarm/Shock bearings done!, Rear Shock overhauled and customised by G-Force, 14-44 Gearing, Exhaust decoked (fun with Caustic Soda!), DEP silencer.