Good luck with that.A gap of nearly an inch?!?!
Start small.
Or did you mean 2mm or .020"
Good luck with that.A gap of nearly an inch?!?!
The capacitor also gives an extra ~400V to the primary of the coil, when the engine is running. This ~400V comes from the voltage spike stored in it. Due to the preceding cycle of the system.<snip>The capacitor used in this distributor is for absorbing voltage spikes caused by magnetic induction and protects the points from burning out prematurely.
Hope this helps.
More to the point, it slows voltage risetime so the points have time to separate beyond the arc quenching distance.Agreed.
Its other function is to prevent sustained arc over when the points open.
Max.
With a 555 driving a grounded gate MOSFET TAC and a "wasted spark" twin lead motorcycle coil, I was able to draw an arc several inches - quite handy for setting fire to bits of cardboard and other items with low thermal inertia.Good luck with that.
Start small.
Or did you mean 2mm or .020"
Agreed, but not with the single "strike" the OP was using.With a 555 driving a grounded gate MOSFET TAC and a "wasted spark" twin lead motorcycle coil, I was able to draw an arc several inches - quite handy for setting fire to bits of cardboard and other items with low thermal inertia.
You can destroy an automotive ignition coil if you don't have the proper size spark gap, as the spark energy has nowhere to go and voltage in the coil secondary will go sky-high so the result is that it might arc over internally in the coil secondary.Gap. > 20mm
Never had that problem with motorcycle coils, and I tried a variety of types when I was experimenting with my grounded gate MOSFET TAC.You can destroy an automotive ignition coil if you don't have the proper size spark gap, as the spark energy has nowhere to go and voltage in the coil secondary will go sky-high so the result is that it might arc over internally in the coil secondary.
For the most part, in the English speaking world the term Condenser became obsolete around the 1950's in favour of Capacitor in what was considered a more accurate description.EDIT: Please note the capacitor in this circuit IS NOT LIKE THE REGULAR AUTOMOTIVE CONDENSER.
Steam tractors have condensers, they also have wheels - you can see where some confusion might arise.For the most part, in the English speaking world the term Condenser became obsolete around the 1950's in favour of Capacitor in what was considered a more accurate description.
For some reason the automotive field did not follow suit and still uses the term to this day.
Max.
Actually, the automotive world does still use the term condenser. It is a heat exchanger used in an air conditioning system. Not sure what books you read or where the information comes from, but we use the term capacitor when reference to the electrical component is necessary. Condenser may be used by the really old techs, but since we don't use ignition points anymore, such does not exist. Capacitor it is!For some reason the automotive field did not follow suit and still uses the term to this day.
I was not referring to anything non electric/electronic, the subject of the post was ignition coils, just pointing out it was continued to be used in the automotive industry long after it was dropped in other electric/electronic fields, in fact several previous posters used the term also!Actually, the automotive world does still use the term condenser. It is a heat exchanger used in an air conditioning system.
Yes, I've always wondered why they kept calling them condensers. But what I meant by that statement was that the capacitor in the dimmer circuit doesn't serve the same purpose as the capacitor (condenser) in the automotive circuit.For the most part, in the English speaking world the term Condenser became obsolete around the 1950's in favour of Capacitor in what was considered a more accurate description.
For some reason the automotive field did not follow suit and still uses the term to this day.
Max.
It condenses the spark at the points down to a smaller size.Yes, I've always wondered why they kept calling them condensers. But what I meant by that statement was that the capacitor in the dimmer circuit doesn't serve the same purpose as the capacitor (condenser) in the automotive circuit.
That seems like a stretch as far as being why they call it a condenser.It condenses the spark at the points down to a smaller size.
ITYMF the lack of pitting on points with faulty or removed capacitor is mostly due to the owner finding the engine runs so badly that its easier to walk!That seems like a stretch as far as being why they call it a condenser.
If sized properly, it prevents a spark from forming at the points at all -- upon opening anyway.
Since the voltage can't change across the capacitor (and if you buy a replacement in an auto parts store they are almost always labeled as condensers) instantaneously, the voltage across the points has to change continuously, starting from zero, as the points open. As the voltage builds in the capacitor, so does the voltage across the point gap. But the point gap is widening while, at the same time, the energy is being expended in the spark at the plug. If the capacitor is big enough, the voltage across the point gap never reaches the value needed to create a spark. If the capacitor is too big, it will rob too much of the energy and reduce the spark strength. As the points close, they are closing on a charged capacitor and that is when any spark happens and also when you get the greatest current through the points as it rapidly discharges that cap. The smaller the cap, the less energy has to be dumped, but the higher the voltage it will have charged to and, hence, the earlier in the closing motion the arc will strike. Its primarily this arc that pits the points in normal operation, as indicated by the much smaller pits compared to those seen when the condenser fails or is removed.
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As the points close, they are closing on a charged capacitor and that is when any spark happens ...
Yep, you misread it. I specifically stated many times that I was talking about the points gap.Did I mis-read that? The ignition spark happens when the points OPEN.
The points cap has little effect on spark intensity at all. It's primary function is to reduce points arcing when the points open, to increase points contact life and reduce RFI.