Huh. I wonder, then, why we crank the voltage/amperage on a welder to make a hotter arc? A weak spark's heat can be absorbed by the electrodes and the fuel/air charge, so a higher spark voltage, which raises the current flow across the gap, makes a hotter spark. Anyone who has replaced an old popint/condenser distributor with an electronic one knows that the engine runs much better. Dan
Huh. I wonder, then, why we crank the voltage/amperage on a welder to make a hotter arc? A weak spark's heat can be absorbed by the electrodes and the fuel/air charge, so a higher spark voltage, which raises the current flow across the gap, makes a hotter spark. Anyone who has replaced an old points/condenser distributor with an electronic one knows that the engine runs much better. Dan
You got to be kidding.
This is a single shot
Regards,
Boris Mohar
Got Knock? - see: Viatrack Printed Circuit Designs (among other things)
void _-void-_ in the obvious place
The current flow in the gap determines "hot".
On some of the CD types I designed we measured AMPERES !!
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
How often have you welded with an ignition coil and a spark plug? or, put another way Is it the object of the spark plug to join two pieces of metal together?
Are you certain that both voltage and amperage go up? Have you actually measured secondary current under varying voltage requirements?
They may well, but it's because the electronics are not subject to degradation due to wear and that the electronics themselves lend themselves to more accurate operation at higher speed than a mechanical system does, but having done the actual measurements between the two types of systems, rest assured, an electronic ignition will have the exact same firing voltage and spark line voltage as a points system when installed in the same engine operated under the same conditions.
Object all you want, I'm only passing along what those who've made ignition systems and their diagnosis their lifes work say.
Okay, it proves what?
If I increase the spark gap, am I increasing or decreasing the circuit resistance?
If you increase the spark gap, you increase the circuit resistance, since air is a dielectric. If you increase spark voltage, you increase spark amperage, according to Ohm's Law. Old points/condenser spark systems were stuck with a maximum 12-volt primary pulse, while the electronic (or even the capacitive-discharge) systems can boost the primary voltage above that, increasing the secondary's output, and since we don't have the points, we get away from the fixed dwell problem (caused by the need to have at least SOME points gap, and time to close them again) and can let the coil build a stronger field before the ignition occurs. I have a Ford 300. Taking the old points distributor and connecting it to a coil and battery and spinning the distributor gear, I got a much smaller spark than I did with the electronic system I stuck in it. It would jump a much bigger gap, indicating a higher spark voltage. Same 12 volt input.
Dan
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.