No tach signal with Dina S ignition

[mark]

I have a MS V3.83 and have installed it on a 1974 Z1 900 Kawasaki, 4cyl in line, duel coil wasted spark, it has a DINA S electronic aftermarket ignition which has duel pickups, the rotor has a single magnet so I believe they must be hall sensors but not sure if its an open collector or built in pullup type, each sensor is grounded to the base plate and has two wires coming off them, one is 12v and the other goes to the negative side of the coil.
I've searched the MisroSquart instructions, ignition setup and the forum for answers and tried a couple of things but still no tach input signal.
Maybe I need to isolate each pickup and earth them to the MS3 earth pin 20 and the signal wires to VR1IN- and VR2IN- and disregard VR1IN+ and VR2IN+?
Any help would appreciated.
Cheers.

[24c]

Mark,

It's a Dyna S... info here
http://www.z1enterprises.com/Documents/ ... ctions.pdf

So it looks like they make a ground, to trigger the coils in wasted spark fashion, 180º apart... 1&4 then 2&3.

Does this help?
Mike

[mark]

Thanks Mike but no it doesn't help
Cheers
Mark.

[24c]

Mark,

Looking at the Dyna S system, it is a dual crank sensor set up. So it's a 1a in the Dual Spark section of the documentation.

"If you have an even fire engine, then try to make the input sensors 180° apart (i.e. directly opposite). With independent dual inputs and outputs, the odd-fire angle is generally built into the sensor location from the factory to reflect the offset in firing of the two cylinder banks. If this is the case, do NOT set the second output offset (odd angle) under Advanced Ignition menu. Otherwise the offset would be applied twice, which would not be correct."

These signals ground the coils, so you'll have to use a pull up resistor set up to make a positive voltage, that'll register as a tach signal. If I understand the pdf correctly, you have advance weights that vary the magnet position, so you just need to lock this out, and you'll have the desired trigger.

This is an atypical pull up illustration, the "push switch to ground " is your Dyna S coil (-ve) connection. The input pin is your tach feed

pull_up.png (20.51 KiB) Viewed 2471 times

I hope this helps
Mike

[mark]

Hi Mike
My knowledge on electronics is very limited and I'm struggling to understand the illustration.
I'm assuming that Vcc is 12v, 10k is a 10000 OHM resister, the switch looking thingy is the Dina S pickup, which goes to ground.
Also, The black wire (for 1&4 cyl) from the Dina S pickup (input pin in diagram)goes to VR1IN+ and the other green wire for (2&3 cyl) goes toVR2IN+. Dose VR1IN- & VR2IN- connect to earth along with the coax shield?
cheers
Mark.

[24c]

Mark,
Lets start again.
What MicroSquirt do you have?
Ignoring your microsquirt when you connect the outputs of the Dina S?
First the black and then the green wire separately, what does it register on a voltmeter? I am assuming you connect the 12V to the + or red terminal on the voltmeter , and the green or black wire to the "common" or black terminal
Are you getting 0 or 12V when the timing sensors line up and the engine is rotating (by hand)?

[EWflyer]

Shouldn't this signal (Coil negative) be input to the Microsquirt through the OPTO circuit rather than the VRIN?

It's a square signal (digital), right? It's closer to what a Hall sensor delivers (1 or 0), rather than an analog signal like what a variable reluctance sensor generates.

[dontz125]

The uS V3 has the MAX9926 VR chip, that apparently does a better job with square-wave inputs than the opto circuit.

[24c]

Guys,
Looking at the schematic of the Dina S? I think it breaks the coil to ground. It's already a processed output, so it is like an electronic set of points (Kettering) i think, so Mark should get an ON/OFF type signal aka like dontz125 says is a square wave.

However, I don't know what unit Mark is using, or what the outputs are doing in reality, hence my questions. If he has a v3 or a v2 (set to LLO), it won't be able to switch the coils directly, and he could have issues with the shared ground on the v2 input circuits too.

Mike

[mark]

Hi guys
Sorry for my absence, and thank you for your advice, This is my 1st attempt at fuel injection and after realising what a steep learning curve I had in front of me I decided to go the coil negative for now, learn how to tune the fuelling then quickly move on to the ignition control which I expected to be doing by now, however on connecting OPTOIN+ to coil- and OPTOIN- to 12v, I fried the 681 resister (R20) on my MS3, I've since replaced it with a through hole, 1/2 to 1 watt resistor of the same resistance amount and loaded the MS2/extra firmware (advice from Matt Cramer DIY AT) everything is working as it should, motor starts and idles beautifully, but for some reason it cuts out after a couple of minutes 4 or 5 times then the TS tells me its disconnected from the MS3, I restart MS3 and it all happens again.
So I'm stumped for the moment and can't move on, any advice would be appreciated.
Cheers Mark.