how do igniters work?
 

how do the igniters work on the fb electronic dizzy?

Find a TII. :D

The ignitor is a transistor that turns a coil on and off quickly (kettering). It is controlled by the pickup which sends it a pulse whenever a reluctor tip passes by it.

here a prior post from this dude.

https://www.rx7club.com/forum/showth...hreadid=202202


Its hard to tell if he is for real OR just trying to be ?????
what a loser.


:uzi: :bsflag:

well it's realy easy to think of the whole ignition system as a circuit. you have power. lets say for the sake of making it easy to understand and universal. you get power from battery. run it to the coil. run the power to the signal pick up in the crank angle sensor(this is the distributor with ouit the distribution). the signal pick up has 2 contacts on it. one right above the other. run the power from the coil to one contact and then run the negative to the other contact. run that negative to the coil. now you have a circuit with a switch in it. the circuit as is is an open circuit meaning it isn't complete so electricity can't flow. so to make the coil fire then stop and repeat this. on the shaft of the crank angle sensor you have a thing like looks like a ninja star. this star has 4 points on it. the signal pick up is the switch. when a point on the ninja star runs by the signal pick up is touches both contacts at the same time. this closes the circuit and lets electricity flow. once the point passes the signal pick up, it opens the circuit causing the electricity to flow. this repeats.

as in the case of a TII and all other rx'7. there is a trailing coil and leading coil. so there is a trail signal pick up and leading signal pick up. both operate the same way. in the case of first gens with plug fires is determined by the rotor and distributor.

13B4port, so the igniter is just a big transistor? the haynes manual called it a "brain box" so i thought there might be some more advanced circuitry. also, i thought the electronic dizzys didnt have contacts that touched each other....im not a ignition expert but it would make sense to me to just have a coil or magnet go past the pickup coil that way no parts touch each other and it would last a long time.....maybe i just misread your post, correct me if im wrong.

and wackyracer you can go fuck yourself, im just trying to learn, is there something wrong with that? and god forbid i didnt know what a TII was, is that supposed to be implanted in your brain when your born along with how igniters work?

then start using search....use your brain...its ok to be a nooobie but being lazy to do research is something else. yo mama aint here to do things for you.

dumb ass.

The voltage spike produced by the action of the rotor passing through the magnetic field in the distributor is too small to trigger the coil(s) unless it is amplified by the ignitor, which is also properly referred to as an amplifier. That's about it, there's no complex engine control circuitry inside. Jeff 20B had it right. Oh, and there is no contact between the parts of the pickup in the distributor.

Wackyracer, you seem to want to start a lot of trouble with people, yet I don't see you adding any pearls of wisdom, just a lot of condemnation. How does your nit-picking people's posts make this a better forum? This is thrice now in the last couple of days that I've seen you being a total jerk to people. You getting enough fiber? Maybe YO MAMA can bake you some bran muffins, I don't know...

your right on that wankel...i just noticed that. I cant tell you much except I have been annoyed with guys who dont wanna spend time doing research. they continued to disregard the warning to do search prior to posting a questions. its using too much bandwidth and most of the time, we can even get it. I can contribute but I just refused since majority of the questions have been asked before.

But hey, thanks for bringing it up. :bigthumb:

Ironically enough, while people keep saying that not searching wastes bandwidth, that's not the case.

Searching actually consumes more bandwidth because of the number of pages that must go down the pipe to find what you're looking for (unless you get lucky)

Posting questions that have easy answers does, however, consume hard drive space and contribute to general clutter in the forum.

So, wackyracer, though I also get annoyed with common questions (despite that fact that I'm still very much a 'noob'), I think we can all be a little cooler about it.


Just my .02

Do you promise to do a search before posting? ;)

I promise!

:D :beerchug:

I always wondered how those igniters worked - thanks guys!

Ray

and the number of pages it must go down is so large because of...? take it from here wacky.

and????
theres still no excuse for doing search!!!! At least I dont post BS.

arg, because of people nto doing searches and posting alot of the saem stuff over and over again. i wonder in total just ho wmany times even that stupid purple custom kit has vbeen posted were the heck are the mods to taek some any control of this stuff plz.

ok first off all, wackyracer, i did do a search, i found alot of things about checking igniters, buying ignitors, igniter problems, but nothing about how they actually work. Everyone was a newbie at some point, and the only way out of it is to ask queations and experiment.

hey wankelguy, so the igniter is just a little amp, so the pulse turns on the transistor creates a more powerful pulse from the battery? then that pulse triggers the coil. i read a post where some guys got working igniters for a few bucks from a junk yard when they are a few hundred to buy new. thats awesome, im gonna go look for some:)

Thanks to everyone, I didn't know how they worked either..learn something new every day.

That IS what the forum's for, after all..

No, Wankelguy's somewhat off base on this one.

This is how it works... An ignition coil consists of a primary winding and a secondary winding. When 12V is fed into the primary winding it creates a magnetic field. When the circuit is switched off rapidly it causes the magnetic field to collapse which induces a voltage into the secondary winding. Because the secondary winding has far more turns the voltage is much greater and that's what fires the spark plugs.

The switching on and off of the circuit is done by the ignitor and pickup. Basically, current flows through the + terminal to the primary winding, out through the - terminal and completes it's current path to ground through the ignitor. The ignitor is told when to turn on and off by the reluctor and pickup.

There is no amplification or anything like that. The ignitor/transistor simply acts as a switch on the negative side of the coil that rapidly turns the circuit on and off.

oh ok. i get it now. thanks to all :)

ahh that makes alot more sence thanks "now i know, and knowing is half the battle)

my bad. i should have read you're post more carefully. i told you how my 13b in my 84 gsl-se works. and how other cars with distributors work.

again sry, plz don't pumel and dis-own me.

Look up "DC Amplifier". :D

But yes, I am frequently "off base", nyuk nyuk.

Wackyracer, my regards to you for hearing me out without taking offense. :bigthumb:

NP. Consider all my input as "constructive criticsm".
:beerchug:

It's "criticism". :rlaugh:

Look, if you're saying there's some sort of amplification of the DC pulse from the pickup to control the transistor then you may be right. I honestly have no idea.

This however is utter crap (either that or you didn't explain yourself very well):

There is no amplification of any "pulse" to control the ignition coil. The only job of the ignitor in relation to the coil is to switch off the primary circuit by interrupting it's current path to ground. That's how any Kettering ignition system works whether it's done by contact points or by electronics.

I think what he's saying is that a transistor, by definition, is an amplifier.


However, Wankelguy, it would seem that in this situation only the switching property is being used.

Although, if that were the case, it could explain the price of igniters. (I'm not sure that a simple electronic switch would make them so expensive)

There's an easy way to find out--- With a Voltmeter =)


Just my .02

Not all ignitors are expensive. You can get GM and other manufacturers ignition modules that do the same thing and are way cheaper. Unfortunately they only work with the 80 model electronic ignition where the ignitors are mounted remote from the dizzy.

HAH! I got an 80 dizzy, hahaha!


This first gen forum is becoming more like a second gen forum.... where most people are grumpy... I think the mods hardley check here anymore cause they think were big boys and can solve things ourselves..... I think they may be right...



how 'bout dem' bran muffins?:chef:

:dunce: :titty: :dunce:





:werd:

I'm done with J-109 ignitors. My next ignition projects will use GM ignitors for Leading to give me a spare incase the stock Trailing ever burns out.

You're right, I didn't explain myself very well. I have a habit of trying to put things in simple terms for the sake of brevity and comprehension by people who are not electronic technicians (as I am). However, an amplifier is defined as a device which uses a small input to affect a larger change in output, whether it's configured as a simple transistor switch or not. It still has to be "signal biased" so that the transistor turns on when the voltage spike from the pickup is applied to the base as there is a .7V drop between the base and emitter. Hell, I'm not the one who coined the term "amplifier" with regard to the ignitors, anyway, so don't rake me over the coals about my use of that term. 'Nuff said. And the reason that the Mazda ignitors are so expensive is mostly just price gouging. I bought one new from a Mazda dealer (for my '80 Courier) in about 1983 and the thing was over $100 back then, and was still cheaper than the identical unit sold by Ford! FWIW, I've gotten several ignitors from junkyards and never found a bad one yet. You want to pull them off a car that was wrecked as opposed to rusted and neglected as that indicates that the car was at least running when it got munched, therefore the ignitors were probably working properly.

Yeah, what he said. :)

As far as I can tell, the voltage spike from the pickup can vary in intensity and frequency and all that jazz, but it doesn't affect the output of the ignitor's transistor in a negative way. The only thing that gets worse as RPM rises is the saturation of the coils. They spark less powerfully at higher RPM because there is less time to build up enough... er, juice.

All I know is the ignition stuff I'm spending my hard earned money and time on is still ok at the highest RPM my engines can rev to, so I still sleep well at night.

Thanks for the explanation, you obviously know more about this shit than I do (being an electronics technician and all :D). But the explanation you gave earlier would only confuse someone who has no clue.

Interesting thread. Just wanted to mention this (repeating, to an extent, what Wankleguy said)...
But...there is amplification involved. If the only job of the ignitor was to switch off the current to the primary circuit, they could have used a relay. Problem is, the relay coil could not be triggered by the very small induced current from the reluctor (the pulse). A transistor can sense the small current from the reluctor and react by varying a larger current: by any definition, that's amplification. Just like an audio amplifier, but without the tunes...

But I do see your point, in that the ignitor is simply triggered by the distributor signal and not "amplifying" the ignition coil signal (current) in any way. The turns ratio in the coil does that, as you've said.

In the end, I'd say both you and Wankleguy (and Jeff20B) are right. The ignitor performs both functions: amplification and switching. :)

It's off topic, but I want your car. Badly. Mind if I drop by one day and have a drive? ;)

-John.

Yeah, I understand what you guys are saying. I didn't really think of it in the sense of amplification because it's indirect. As for using a relay, that would impossible anyway because it wouldn't be able to perform fast enough.

If you wanna have a drive you're welcome to come over and visit any time. ;)

Quite right. The relay was an example as to why the transistor (ignitor) works, and other options don't.

Why, thanks! Wish to Hell I could. :) (Now, if you could throw in a meeting with Goldie from Water Rats, I just may swim on down...)

-John.