So maybe a Hairbrain idea, but I have a two cylinder engine that is powered by 12 V ignition system. Power supplied to the mission coil whenever the commissions which is on, ground is switched to create the spark. Basically, conventional ignition system.
I want to power a 3.3 V Arduino with a Bluetooth module off the positive and negative terminals of the coils primary. I want to be able to store enough energy while the engine is running to check for Bluetooth messages that would indicate that should shut off the power to the coil.
So out of curiosity, is this completely insane? I know there would be some radio issues because of the incredible noise from being so close to the engine, but I was wondering if anyone thinks this is even possible with large caps and some good isolation diodes?
Any feedback would be awesome
spenc2017:
So maybe a Hairbrain idea, but I have a two cylinder engine that is powered by 12 V ignition system. Power supplied to the mission coil whenever the commissions which is on, ground is switched to create the spark. Basically, conventional ignition system.
I want to power a 3.3 V Arduino with a Bluetooth module off the positive and negative terminals of the coils primary. I want to be able to store enough energy while the engine is running to check for Bluetooth messages that would indicate that should shut off the power to the coil.
So out of curiosity, is this completely insane? I know there would be some radio issues because of the incredible noise from being so close to the engine, but I was wondering if anyone thinks this is even possible with large caps and some good isolation diodes?
Any feedback would be awesome
If there is no 12 volt battery and charging system, it's hardly a conventional 12 volt ignition system. If so, how do you know it's 12 volts?
Some small engines have an ignition system based on coils in the flywheel generating an AC voltage which is rectified to provide the base voltage for the ignition system. It also provides voltage for lights, like on a riding lawn mower. They are only 12 volt nominally.
More about the engine's electrical is necessary.
Paul
sorry, I did a poor job of detail.
it is completely a conventional 12V system. has a battery, a psudo charging system, a starter and ignition switch. the signal for the coil is generated from a engine control module, and power for the + side of the coil comes from a fused switches source.
I know there are various ways to do this, but what I was wondering is could it be done with just access to the two wires that supply the coil, putting something inline with these two wires. I know if I had constant power from he battery it would be easy to do, I am just wondering if enough energy could be captured during the "charge" pulse from the eco to the coil and stored to keep the Arduino MCU running and occasionally check the BT module.
does that help better explain the concept?
Ok, that is much better! Thanks.
The hot side of the coil is pretty much a direct short to ground during the magnetic charging time. Certainly won't be 12 volts. Only 12 volts when the ground is opened by the points. You really need a scope to measure the voltage during the charge time and during the open time to get and average to work with.
Paul