Condenser/ Capacitor

[John T]

Jim; I keep saying there is more coming out of a coil than you put into it. In a round about way, you said the same thing!

Teddy it’s a passive energy storage device no way you get more energy out than put in

John T

 

[teddy52food]

Teddy it’s a passive energy storage device no way you get more energy out than put in

John T

Explain why a coil is used to make a better spark in the old hit & miss engines with the ignitor? If you would run that wire straight ,it would not help make a better spark, but in a coil the collapse is more than the imput!

 

[Phill Tibbetts]

I was confused before, now I am totally lost.

 

[Fritz Maurer]

Not being an EE I am somewhat electrically dumb at this level. If you attached leads to this with alligator clips for the purpose of testing a suspected failing ignition condenser you would disconnect it in the distributor and connect this at the coil and run the engine? I suspect long term it is far less rugged and susceptible to failure from vibration, heat and moisture.

Yes, Kohler did exactly that with the K-series with battery ignition for many years. Doesn't matter where it is, could be up under the dashboard; long as it's parallel with the points.

 

[Janicholson]

Explain why a coil is used to make a better spark in the old hit & miss engines with the ignitor? If you would run that wire straight ,it would not help make a better spark, but in a coil the collapse is more than the imput!

The science involved is well documented and practiced across the world in applications from generators/alternators/and rail guns. Even the Large Hadron Collider in Europe believes in the science. A magnet is a passive device, whether electromagnetic, or permanent. The alignment of the flow of electrons, or the alignment of the magnetic domains in a permanent magnet are responsible for an envelope of lines of force. These lines are evident when iron powder is sprinkled on paper under which is a permanent magnet, or a DC electro magnet. They interact with things that include conductors, paramagnetic and magnetic metals, and other magnets, by being deflected in some cases, and if motion is involved with conductors, they generate electricity. There is never any extra energy created. Every example is less than 100% efficient in transferring work to the near by objects/wires. Eddy currents are an example of this, they are small loops of electricity generated in conductors that are mini short circuits, sapping energy from generators and transformers and motors. Insolated iron laminations are a major attempt to limit the absorption of magnetism/work from Eddy currents. The cup shaped driven component of tachometers and speedometers are examples of using Eddy currents to transfer effort from a cable that spins a magnet inside the cup. There is no free lunch. Jim

 

[will-max dairy]

I was confused before, now I am totally lost.

Condenser is just an old name for Capacitor
Condensers are high voltage capacitors.
You can buy industrial grade capacitors with the same voltage rating (in Volts) and capacitance (in Farads... often microFarads (uF)... and use them as a condenser.

If you suspect a failed condenser, you can test it with a meter. The meter will put a test voltage across the condenser and measure its capacitance. This test isn't 100% though, because the test voltage used within the meter will often be low (say 5 or 12 volts); and the condenser might be failing in the ignition at much higher voltage... say 300 Volts. (as an analogy... you could probably test many failed hydraulic lines with 40psi used in a domestic water supply and find no leaks... put it in a 2000psi hydraulic system? and BAM... leaks)

If you replace a "condenser" with a "capacitor"... make sure you get the same rated voltage and capacitance, and try to connect it as closely to the original connection as possible. Good thing is, these types of capacitors are not polarized; so you don't have to worry about that.

There is the summary

 

[will-max dairy]

If you don't want to memorize all of that... just buy a bunch of condensers and keep them on hand... when you do maintenance and change condensers... substitute until one works. Sad that it has come to that, but it has.

 

[Janicholson]

Explain why a coil is used to make a better spark in the old hit & miss engines with the ignitor? If you would run that wire straight ,it would not help make a better spark, but in a coil the collapse is more than the imput!

The igniter coil raises the voltage such that the breaking points in the combustion chamber have a longer spark trail, exposing more fuel/air to the spark, not more total energy. Kettering ignition with points often operates at close to 4 amps. if there was a power gain the spark plug electrodes would be burnt off on a few minutes!! Jim

 

[will-max dairy]

Explain why a coil is used to make a better spark in the old hit & miss engines with the ignitor? If you would run that wire straight ,it would not help make a better spark, but in a coil the collapse is more than the imput!

Short answer... (Primary Voltage rms) X (Primary Current rms) = (Secondary Voltage rms) X (Secondary Current rms)

You put in low voltage at high current... you get out high voltage at low current. As a matter of fact, the above equation assumes 100% transfer of magnetic flux to the secondary... which is ideal and not realized in practice.

If you have ever compared different air compressors for CFM and pressure... you already understand this.

 

[will-max dairy]

Short answer... (Primary Voltage rms) X (Primary Current rms) = (Secondary Voltage rms) X (Secondary Current rms)

You put in low voltage at high current... you get out high voltage at low current. As a matter of fact, the above equation assumes 100% transfer of magnetic flux to the secondary... which is ideal and not realized in practice.

If you have ever rated an air compressor for CFM and pressure... you already understand this.

As a matter of fact... when the condenser gets heated... the energy that heated it was lost in the transfer from primary to secondary... so the fact that you have a condenser is just one point (pun intended) that shows that you get less out of the secondary (energy-wise and power-wise) than you put into the primary.

 

[wore out]

Explain why a coil is used to make a better spark in the old hit & miss engines with the ignitor? If you would run that wire straight ,it would not help make a better spark, but in a coil the collapse is more than the imput!

Current builds up magnetism in the coil's core over TIME (dwell time) and then when the primary circuit is interrupted the magnetic field collapses and induces current in the winding creating a much higher voltage, but of short duration as compared to "dwell time"

 

[will-max dairy]

Current builds up magnetism in the coil's core over TIME (dwell time) and then when the primary circuit is interrupted the magnetic field collapses and induces current in the winding creating a much higher voltage, but of short duration as compared to "dwell time"

in what I said... the "time" factor is accounted for in "rms"... which I'm sure you understand.

 

[Janicholson]

Well its a matter of V=Ldi/dt. The cap just sucks up that V (energy) slowing the rate of rise below the arc point while the secondary rises to the arc over voltage of the plug, completing the circuit for dissipating the energy stored in the coil.

Capacitors give back to the coil primary (ringing) the electrons it absorbs. Other than minor resistance in the "plates" and leads it is passive to dissipation of energy. The return to zero across the points before closing is due to the resistance of conductors and the magnetic reluctance of the coil acting like a choke. Jim

 

[will-max dairy]

I miss Dell and some of the other "old ones" that used to be here.

They would have started talking about voltage in terms of "Tension"...which would blow peoples' minds even more...

"Tension" on a "Condenser".... "Voltage" on a "Capacitor"...

Heck... we may as well start talking about taking the "Heaviside Transform" of the circuit elements...

 

[olddavid]

but in a coil the collapse is more than the imput!

The voltage does get stepped up to fire the plugs but the overall power output cannot exceed the power input to the coil. In other words, the voltage is stepped up, but the current is reduced at the output. If the output voltage had the same current ability as the coil primary draws a spark plug shock would almost always be fatal.

 

[JMOR]

Another view is that the condenser, being in parallel with the points, it provides a momentary path for coil current to continue to flow as points open & having this alternate path, reduces the arc across the points. I made a video awhile back (~5 tears) using a 55 microFarad cap vs the normal 0.22 microFarad unit and the engine ran. Disconnected the cap while engine running and engine died....reconnect during coast down and it restarts. If you can't hear the sound, engine run, not run, most is lost.

https://imgur.com/m84PvvB

...and a visual of same:

https://imgur.com/PlWz4qF

https://imgur.com/TwoB4Ob

 

[stdsch40]

I've made my own set up, for experimtal purposes, using 12vdc tractor coil, 12v battery, 20ampDC solid state relay (SSR), spark plug, and Arduino nano to generate semi continouous spark at the plug. No capacitor/condenser was required using the solid state 'switch'. The SSR worked fine being switched on and off at 0.1msec intervals from the arduino nano. Not sure a lesser amp rated SSR would do the job cuz I didn't have one. My set up worked like a charm.

 

[John T]

Explain why a coil is used to make a better spark in the old hit & miss engines with the ignitor? If you would run that wire straight ,it would not help make a better spark, but in a coil the collapse is more than the imput!

A coil can be used to step up voltage via transforner action but it can not step up energy in versus energy out. Which is volts x amps x time period.

Al are entitled to their own opinion and mine is a coil or condensor or whatever can’t create energy only charge it’s form and you can’t get more energy out then put in period

We will just have to agree to disagree with all due mutual respect in this one I don’t feel like nor can I explain a lifelong study and practice or ee 101 or the laws of physics here

Best wishes I respect your right to your opinion on this

John T

 

[John T]

I’m here late the second wave and don’t feel like saying much more and glad I was late lol. Physics and ignition theory abd ee 101 can’t be explained here, some know it others don’t and that’s nothing to be ashamed of. An electronic device cant create energy that’s my opinion and I’m sticking to it but allow others different opinions it’s a free country.

John T

 

[John T]

What you say is true, zero voltage 120 times a second and 60 times a second + 155 peak volts and another 60 times a second -155 peak volts and the current is many times more on a pump vs 4 amps on a coil.

I know what happens without a condenser. In 5 miles the points on my motorcycle were toast.
I wonder how many people think they can't buy good points anymore when perhaps the condenser isn't good or too small?

Yep when points are closed and it conducts it’s about 4 amps at 12 volts. When it stops conducting the hv secondary can be several thousand volts but lowww amps and of course it can’t create energy !!! But you know physics and already know that George