Ignition circuit help

[Lakc]

Lakc:

Messy ??

Looks like the place blew up

Looks like you're on your way.

Can you activate the circuit with a pulse generator (555) or I guess since you have the uP you could have it activate itself.

Sometimes (most often) things go bad fast when you generate a lot of sparks in a hurry. RFI EMI power supply failure....

It's really satisfying to hear (and see) the circuit generate sparks at engine frequencies. (he says biting his tongue )


Sage

It would actually be easier to grab another pic and make that trigger the circuit, but thats in future testing. The flyback transformer is still in "safe mode", choked on the feed side and a 12ohm resistor on the drive side just to avoid any thermal issues until I get the duty cycle and control circuit proofed. Currently its at ~30khz and only around 20% duty cycle. There are plans to eventually have it vary its own duty cycle based on load. I also have temperature feedback provisions for the driving mosfet to add in. So many of these self destruct or blow out their own hall sensors, I wanted to build a bulletproof one.

 

[canadianhorsepower]

Well well well. Another day of trying and calling and email. With some deffinite answers.
On a GM I was abble to get a 6cyl ignition module for a DIS. I wanage to simulate it with the all sensor
worked fine. When I notice this I whent ahead remove one coil and simply put a 120 60 watt bulb
across the coil terminal then I decide to turn on my motor that buld simply exploded. All I had left
was a socketth_wtf1 happend here. I remove the light socket and decide to use a multimeter on Very
high scale DAMN it peeking 480 volts:fan: no wonder it did "electrocute my 120 vbulb"Rof}Rof}
that was one input 480 volts. Then i did a voltage divider with a potentiometer, hook it up to the scope

and guess what it's pulsing at 6hz. Then I decide to try a single Gm module the one with 4 wires:wall:

no it didn't work I fried the module. That was enought experimenting for today. I called my freind at BRP

trying to get a module and diagram they were using in the 80. on anything with twin cyl and one coil:shrug: waiting for him

 

[canadianhorsepower]

These can be another avenue
http://www.ebay.com/itm/KAWASAKI-75..._Watercraft_Parts&hash=item43b8f083f2&vxp=mtr

 

[canadianhorsepower]

http://www.autotap.com/techlibrary/understanding_multi-coil_ignition_systems.asp

bed table reading

 

[stevehuckss396]

These can be another avenue
http://www.ebay.com/itm/KAWASAKI-75..._Watercraft_Parts&hash=item43b8f083f2&vxp=mtr

Those are the same avenue. That looks like what I have. Could be the exact same coil.

 

[Lakc]

Well well well. Another day of trying and calling and email. With some deffinite answers.
On a GM I was abble to get a 6cyl ignition module for a DIS. I wanage to simulate it with the all sensor
worked fine. When I notice this I whent ahead remove one coil and simply put a 120 60 watt bulb
across the coil terminal then I decide to turn on my motor that buld simply exploded. All I had left
was a socketth_wtf1 happend here. I remove the light socket and decide to use a multimeter on Very
high scale DAMN it peeking 480 volts:fan: no wonder it did "electrocute my 120 vbulb"Rof}Rof}
that was one input 480 volts. Then i did a voltage divider with a potentiometer, hook it up to the scope

and guess what it's pulsing at 6hz. Then I decide to try a single Gm module the one with 4 wires:wall:

no it didn't work I fried the module. That was enought experimenting for today. I called my freind at BRP

trying to get a module and diagram they were using in the 80. on anything with twin cyl and one coil:shrug: waiting for him

Rule of thumb is that with any automotive coil you expect a 450v primary kick.
Just like with fuel injectors, some of the newer OBD systems use Zener diodes to actively check the coil status. Although 75v is what you usually get from an injector.

 

[Lakc]

Those are the same avenue. That looks like what I have. Could be the exact same coil.

Thats yoru problem, they are jetski coils, they only work underwater

 

[stevehuckss396]

Thats yoru problem, they are jetski coils, they only work underwater

Snowmobile and Jet ski coil. So it should work under water and in the snow.

 

[Lakc]

If this is what it looks like installed, which makes sense as there were no spark plug boots or terminals, and assuming this outfit isnt putting their own ignition system in it, that box looks like it says CDI... Never heard of a CDI "only" coil before, but its beginning to look like a possibility.

 

[canadianhorsepower]

[/QUORule of thumb is that with any automotive coil you expect a 450v primary kick.
Just like with fuel injectors, some of the newer OBD systems use Zener diodes to actively check the coil status. Although 75v is what you usually get from an injector.
__________________
TE] all other system from Gm works on 12 volts

 

[canadianhorsepower]

Snowmobile and Jet ski coil. So it should work under water and in the snow.

Steve I agree with you ,a coil is a coil it dosn't know what turn it on

just like men, a men is a men and no one know's what turn them on
brunette or blondyRof}Rof}

 

[Lakc]

Rule of thumb is that with any automotive coil you expect a 450v primary kick.
Just like with fuel injectors, some of the newer OBD systems use Zener diodes to actively check the coil status. Although 75v is what you usually get from an injector.
__________________

all other system from Gm works on 12 volts

It all works on 12 (14.7) volts. But to be emissions compliant they use the backward kick from the coils to tell the ECU that it fired correctly. Usually a zener diode breaking down which charges a small cap to allow a digital input pin to register the event took place properly.

Steve, if this is a special coil for a CDI system, the circuit your working might not be able to fire it. There are a bunch of transistorized automotive coils that could take its place, or hopefully my planB will be ready soon. My mkI system should fire it, and your welcome to try that this weekend if you like. MkII is firing, and I straightened out the cap charge in software tonight, but its not ready for prime time yet.

 

[Lakc]

http://www.sportdevices.com/rpm_readings/CDI_and_TCI.htm

Well, at least according to that site, they do make special coils for CDI. I have a nice museum piece General Radio induction meter, will be interesting to see exactly what that coil is made of.

 

[canadianhorsepower]

http://www.sportdevices.com/rpm_readings/CDI_and_TCI.htm

Well, at least according to that site, they do make special coils for CDI. I have a nice museum piece General Radio induction meter, will be interesting to see exactly what that coil is made of.

My GM coil have .6 ohms

 

[stevehuckss396]

This weekend is bad. Have to cut over a UPS system at a data center and it will be a "late night when computer traffic is low" kind of thing.

 

[canadianhorsepower]

This weekend is bad. Have to cut over a UPS system at a data center and it will be a "late night when computer traffic is low" kind of thing.

burk, Steve . why dont you try soldering or making a why of ht wires
and run a regular coil and see what happen. After all that nasty coil beside
being a CDI unit its plain coil with 2 out. And theory should make it spark where teir is gas and air not only air

 

[dsage]

CHP:

Maybe I mis-understood what you wrote but:
If you fire both plugs with a HV Wye connection from one coil, the spark will occur in the cylinder with no compression, leaving nothing for the one that requires the spark.
Path of lease resistance. Firing a plug under compression not to mention with a fuel mixture, takes many times the voltage to fire than a plug at atmospheric pressure.
The dual output coil expects the plug(s) to be connected between the HV leads (like a common transformer). It does not fire to ground. If you have two plugs, they are effectively in series when screwed into the same block. Being a series circuit the one with no compression fires easily passing the voltage (current) on to the other plug.

Sage

 

[Lakc]

This weekend is bad. Have to cut over a UPS system at a data center and it will be a "late night when computer traffic is low" kind of thing.

One of those "plenty of coffee nights", yeech.
I wasnt happy with my MkI but it might just be the trick for a real CDI coil. (Or maybe your coil would be the trick for my engine?) We just need to get it working first, we can make whatever fit later.

 

[canadianhorsepower]

If you fire both plugs with a HV Wye connection from one coil, the spark will occur in the cylinder with no compression, leaving nothing for the one that requires the spark.

What is the best insulation air gap, It will jump where its easier.
I agree with you If one cylinder is under compression no gas mix and the other one no pressure
and no gas mix it would take that path
gas and mix are an explosive all they are waiting for is a spark and it does not have to be big

 

[stevehuckss396]

What is the best insulation air gap, It will jump where its easier.
I agree with you If one cylinder is under compression no gas mix and the other one no pressure
and no gas mix it would take that path
gas and mix are an explosive all they are waiting for is a spark and it does not have to be big

I have heard the same thing Sage has presented. I have to believe that if the Y cable worked like you say, there would be engines out there with Y cables on them. Putting the plugs in series forces the spark in the compressed cylinder.