It works at a lower voltage because the inductive field has to collapse very quickly to give highest voltage. It cannot do that if the points are sparking.
I am well aware that you will get a ringing waveform when the field collapses.
I have never tried it, actually, but concede that if it should start at all, it wouldnt run for long. Have you actually ever tried this?
I did. It won't run.
Dan
Not usually. If there is a spark plug that fires the wave form gets arrested before it reaches maximum on it first peak. Only if there is no diversion of the current (by arcing in the secondary) will there be the damped sinusoidal waveform.
Oh sure I have. Remember the type of points that had a condenser wire that just slipped in behind the points spring. After installing new points I once put the distributor cap and pinched the condenser wire between the cap and distributor. The engine started up and idled fine, but as soon as it was revved up the engine stalled and would not restart. When I open the distributor I found that as soon as the vacuum advance kicked in it pulled the condenser wire out of the circuit and the engine killed. After inserting the condenser wire back where it belonged and carefully routing the wire so that the cap didn't pinch it again the engine started and ran fine. With out the condenser hooked up it had a little spark, but the spark was very weak.
Now I'll admit that the weak spark (low voltage) does have something to do with arcing at the points and you could probably design a set up that got a higher voltage with a different type point and coil configuration. So it may be possible to construct a point set up that worked without a condenser and that set up would probably not last as long. But that has to do with efficiency. The capacitor is sized so that it works efficiently. That is it produces the required high voltage with a minimum amount of current flow. A system without the condenser would require alot more current flow thru the coil to generate the same high voltage output, and thus the points and coil would not last as long.
-jim
I showed this same thing in a different way trying to test the coil on my Sportster motorcycle. Used a plain piece of wire instead of points and condenser, touching the wire to ground manually and pulling it off to create the spark, seen by looking at a spark plug out in the open (grounded to the threads, of course). The spark generated in this manner was so puny it was hardly visible. When I added a condenser the spark was big and audible.
Try he same thing but do the make/break by scratching the wire across a file. Plenty hot spark...
Then again, Chrysler service manuals in the late 70s early 80s showed how to rig up a coil tester that used a condenser in parallel with the make/break wire.
It does. Yes, the charging circuit will WORK without the cap, but the contacts on the relay will erode much faster than when the cap is present. Lots of RFI is a sign that the points are arcing, eliminating or reducing the arcing will make the contact points last longer. No "ifs, ands, or buts."
replying to Bob Flumere, jenglish wrote: perhaps you could help me, recently replaced generator and regulator in 56 Buick and ammeter shows no charge again. flashing for polarity doesn't help anymore. i have a battery disconnect on the ground terminal. with the old generator and regulator if i did the battery disconnect while the engine was running the engine would continue to run until the ignition switch was turned off; since change of generator and regulator when i open the battery disconnect the engine stops; just trying to understand whats going on. any comment?
jenglish wrote in news:egNeD.62028$ snipped-for-privacy@fx31.am:
the first obvious thing is the gen. is not having any output. you need to find out if its the gen or reg that is the problem. KB
thats wrong a alternator acts like a ac magneto in reverse form it can even act as as a bldc motor with a proper controler the gm 4pin ignition module system works on coliding magnetic fields bouth take place in the primery circuit a ac pulse is turned to dc pulse by the ignition module coming from a pick up coil the second pulse comes from the batery exactly from the potential diference from the alternator when those oposing waves hit ich other with high speed for exampel positive and negative pulses hit ich ither you get a spike down the high tension lead you can ither use ac with ac ore dc puls with ac it still will work those are called ac and dc magneto's so that alternator needs a condenser if not you get static in your baterry who will destroy it after some time doe the reson your alternatir is over charging the baterry with more volteg even tought that us not made you get more power considered the ignition system faster working electrical devices like electric motors etc thats the real reason that condenser is there for! those are low reving alternator build for working mashines like tractors if they are put in a car they will over charge a baterry you get a sport car out of your lazy normal ignition system this is considered as a waste spark ignition system as well by fiering on compresion and exaust at the same time your car will have more power
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