grassracer
|
| posted on 27/7/09 at 05:48 PM |
|
|
Resistors in Ignition Circuits
I'm busy wirirng a ZX6r for autograss use and have fitted a 100ohm resistor in the switched live to the cdi, theproblem I have is still no spark
and when I test the circuit I have 12v before the resistor but only 0.6volts immediately after when I test with a multimeter....is this pointing to a
problem with the resistors ( I've tried 2 just in case!) any help gratefully recieved
|
NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
|
|
|
02GF74
|
| posted on 27/7/09 at 06:16 PM |
|
|
quote:
Originally posted by grassracer
have fitted a 100ohm resistor in the switched live to the cdi, theproblem I have is still no spark and when I test the circuit I have 12v before the
resistor but only 0.6volts immediately after when I test with a multimeter....is this pointing to a problem with the resistors ( I've tried 2
just in case!) any help gratefully received
why is the resistor necessary?
dunno what you are trying to do but resistor appears to be working - it is dropping voltage; that gets converted to heat.
resistors fail if they are made to dissipate more heat than intended, usually accompanied by smoke - I have seen them glow red hot for a short
time.
if yours has not gone up in smoke and is not getting too hot to touchm the porlbem lies eslewhere.
|
|
|
grassracer
|
| posted on 27/7/09 at 07:03 PM |
|
|
The resistor is needed to drop 12v supply down to a 9v supply for the coils to operate so I'm led to believe
|
NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
|
britishtrident
|
| posted on 27/7/09 at 07:42 PM |
|
|
You need a much lower resistance ballast resistor ---- not sure exactltywhat is required for your coil but I suspect it will be in the range of 1
to 6 ohms
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
02GF74
|
| posted on 27/7/09 at 07:59 PM |
|
|
quote:
Originally posted by grassracer
The resistor is needed to drop 12v supply down to a 9v supply for the coils to operate so I'm led to believe
so like a ballast resistor?
without knowing you coil spec. 100 is way too high.
if you can measure resistance of coil, then the ballast would be 1/3 of that value that to drop 3 V, leaving 9 V across the coil.
The resistance of the coil would be around 1.5 ohm (not more than 3 ohm for sure) so resistor is very small value, closer to 1 ohm than 100 ohm.
Check the power rating -you'd been looking at quite a few watts or you'll see smoke.
|
|
|
yorkshire-engines
|
| posted on 27/7/09 at 10:04 PM |
|
|
Hi some of the early carb engines (which you proberbly have ) dont need a resistor to work
the later need a 100 ohm 10 watt resistor between switched live and the grey wire to ecu the voltage drop is 12 to 10 volts
if you have a resistor that is dropping to .6v then its the wrong wattage try one from the kawa ignition lock any model
cheers malc
|
|
|
