Can a small transformer of 3 to 1 ratio be used in reverse for increasing the output of MAGNETO lawn mower ignition coil for a higher high voltage? This is a pulse effect and ground connection , not AC. I located a 120v to 36 v AC small transformer. The magnet wire windings are in plastic bobbin separated from core laminations for insulation. The regular type Voltage multiplier circuit only works with AC. The magnet generates about 5-8 volts into original primary winding,The SS module shorts primary. The primary Back EMF forms -130 volts that runs the secondary, for about -10KV pulse to spark plug + positive ground. (split/tran ST-3-36 PCB mount.) What about a PF capacitor, as much larger ones are used for filter capacitor that normally raise up a power supply DC volts?

 

What we do not know is anything about the magneto as it is before any changes are made. There are several service actions that will restore the output of a magneto to where it should be. If the magneto output is below specifications there are several things that can be addressed.
BUT if the TS has a correctly operating magneto and wants output in excess of the specified amount, that is a different situation.

To restore a weak magneto the first step is to clean and adjust the gap of the breaker point contacts. Usually a replacement for the capacitor in parallel with the points will improve the spark voltage. The contact gap is critical because it affects the timing relative to the breaking of the magnetic flux path. The other variable is the gap between the magnetic parts before the path is broken. The narrower that gap the greater the voltage.
any additional increase would require modifications that will be quite a bit more involved.

What we do not know is what the present configuration of the magneto system is, and there are a number of different systems that have been used over the years.

So the question becomes how much increase is desired, and how much modification the TS is able to do.

 

I'm assuming (possibly wrong) that your magneto is operating like it is supposed to and you are just wanting to get even higher voltage pulses out of it for some reason other than what the magneto was intended for.

Using an off the shelf transformer has two (probably more) major issues with it. First, it is designed to work at a particular frequency. If you take one intended to operate at mains line frequencies, it probably is not going to work well at the frequencies intrinsic is a pulse from a magneto. Second, it is designed to withstand voltages up to a certain amount. A transformer that is designed for 120 VAC may not survive long if you start trying to apply tens of kilovolts across it.

 

I'm assuming (possibly wrong) that your magneto is operating like it is supposed to and you are just wanting to get even higher voltage pulses out of it for some reason other than what the magneto was intended for.

Using an off the shelf transformer has two (probably more) major issues with it. First, it is designed to work at a particular frequency. If you take one intended to operate at mains line frequencies, it probably is not going to work well at the frequencies intrinsic is a pulse from a magneto. Second, it is designed to withstand voltages up to a certain amount. A transformer that is designed for 120 VAC may not survive long if you start trying to apply tens of kilovolts across it.

 

60 cycles is considered a low frequency, and not bothered much with reactance. The lawn mower one cylinder flywheel as a 4 cycle Briggs type , fires at TDC and then is OFF after about 10 milliseconds. The flywheel Magnet energy + coil, is OFF about 90% of the time or more. ( Very low duty cycle) Less heating effect and less of a chance of shorting. The waste spark is there but can be shut down with additional circuit. Mower engine is about 5-15-cycles frequency idle speed. I am also aware of efficiency losses through a transformer. A higher RATIO than needed would be used. Electronic parts are mostly damaged by heat,- not the low current in a high voltage section. Power transformers with steel laminations and TV high frequency ferrite flybacks at 15Khz use the same type of enamel coated insulated magnet wire wrapped side by side. I chose a transformer with coil form plastic bobbin as being an insulated spacing away from metal core. I need information on how to figure out how to increase the high voltage output , and continue using the provided embedded magnet. I'd rather not have to disassemble the system for modification to 12v DC electric ignition coil. The twin cyl Briggs type, has one coil with one SS trigger module, and 2 output high voltage cables. Maybe that could be mounted for an AC effect , so that the common voltage multiplier can be applied? Negative + positive with diodes added? What do you think?

 

I have no idea what to think because you still haven't given any indication of what the problem is that you are trying to solve. Why are you doing this? If the ignition system on this engine isn't working properly, why not fix the ignition system back to the way it is supposed to be? If you are trying to do something other than get the ignition system working, what is it you are trying to do?

 

Can a small transformer of 3 to 1 ratio be used in reverse for increasing the output of MAGNETO lawn mower ignition coil for a higher high voltage?

Where/how do you propose inserting that into the magneto system? The low voltage winding of the coil is part of an auto transformer, so inseparable from the high voltage winding.
With the magneto that you have, the only way I can see of increasing the HT would be to completely rewind the coil or increase the magnet strength.

 

60 cycles is considered a low frequency, and not bothered much with reactance. The lawn mower one cylinder flywheel as a 4 cycle Briggs type , fires at TDC and then is OFF after about 10 milliseconds. The flywheel Magnet energy + coil, is OFF about 90% of the time or more. ( Very low duty cycle) Less heating effect and less of a chance of shorting. The waste spark is there but can be shut down with additional circuit. Mower engine is about 5-15-cycles frequency idle speed. I am also aware of efficiency losses through a transformer. A higher RATIO than needed would be used. Electronic parts are mostly damaged by heat,- not the low current in a high voltage section. Power transformers with steel laminations and TV high frequency ferrite flybacks at 15Khz use the same type of enamel coated insulated magnet wire wrapped side by side. I chose a transformer with coil form plastic bobbin as being an insulated spacing away from metal core. I need information on how to figure out how to increase the high voltage output , and continue using the provided embedded magnet. I'd rather not have to disassemble the system for modification to 12v DC electric ignition coil. The twin cyl Briggs type, has one coil with one SS trigger module, and 2 output high voltage cables. Maybe that could be mounted for an AC effect , so that the common voltage multiplier can be applied? Negative + positive with diodes added? What do you think?

There are at least 3 generations of ignition systems on the Briggs and Straton one cylinder engine, and we have no hint as to which one the TS seeks to modify. The connections in the spark system of each are quite different. Which version is the TS seeking to change? That matters a lot.

And there is also an access issue because in every engine that I have worked on the entire coil system is encased in a molded plastic case, which not only makes it waterproof and vibration resistant, but also makes it very difficult to access any of the connections.

And as to the insulation concerns, there is a great deal more than just the turn to turn voltage consideration in high voltage assemblies. TV CRT flyback transformers have been very carefully arranged to get around the limitations of the insulation used.

 

Other methods to increase ignition voltage can be insertion into a pulse type, step up transformer, laminations type, with the ratio desired . Since ignition is just pulse voltage out one direction and not AC, the common multiplier circuit can't be used. The other method is to add accessory spark gap with attached PF capacitors in and hooked to air core copper coils transformer of about 1:3 ratio. (Small voltage type Tesla coil / Tesla hair pin circuit with Radiant Energy) The reasoning behind this , is that the lawn mower SS ignition coil (Magnetron) is only 10kv and not strong enough voltage to perform PLASMA PATH for the expected DC current injection into spark plug. S1R9A9M9 - Nathren and his tech people either did that Tesla circuit, or just used a PF PEAKING CAPACITOR . But that is a very short time constant compared with ignition volts. The whole idea was to allow extended time constant for about 34% ON TIME of circuit not just near TDC.This allows more DC current contact with water and water vapor . The 1978 car got 18MPG on water but was using HEI as about 28KV from high energy ignition chevy coil in top of distributor cap, as good Plasma Path. My bench project has small board with inverter to DC high frequency type with bridge rectification charging 47Uf cap with 200v output through 15kv block microwave diode. This is against the ignition high volts output , so as not having to increase the original 10KV. The cap discharges with Radiant Energy allowing plasma path. ( An increase of string series protection diodes bank requires much more input draw current and wattage from input battery.) It's best to keep the ignition volts at a lower level. The succesful Briggs demonstration of 2008 , S1R9A9M9 Youtube videos 1+2 , had no protection at all. Battery could have exploded. The 2 showings were just quick set ups to show it was possible to run an engine on water in carburetor from spark plug electrolysis and water vapor pressure.

 

Post #9 reminds me of a request made by a scientist, (Gorden Fenn), to provide a much more powerful ignition spark for an engine experiment. The request was for "10,000 volts at one amp" to properly ignite a lean mixture. Our evaluation was that this would be running the engine on pure spark. It would be possible to eliminate all carbon emissions. The challenge would be the source of the 80 kilowatt ignition power to run the V8 engine.