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My old voltage regulator had died and i've build one Voltage Regulator and it work, i've tested with a variable DC power supply.The charging maximum voltage is set around ~13.77V (below the DF have signal, upper doesn't have, i've connect an LED to make it more visual).

Connected to my ETZ 250, D+ to contact relay, D- to ground(GND) and DF to the alternator rotor coil. With the engine on and varying the revs the voltage increase to ~35V.as high is the RPM higher is the voltage.
I take down the regulator and check it again, but all was ok. With the regulator down i've start the engine and the voltage still climbing with the RPM. The rotor coil wasn't any supply and to make sure i've connected to the ground both end of rotor coil.
I haven't any clue what's happening. The biggest problem is that the modules driven by microcontrollers collapse (turn signal, park light, brake light doesn't work properly).
I'm thinking of ignition coil can cause this ... but i'm not sure. At this moment i doesn't have any other ignition coil to test(i have one from Opel Astra F(C16NZ) but the resistance at primary coil is ~0.4 ohm which is too low for my ignition module and the final transistor get hot in no time).

Here is my ignition module schematic:


It is possible to be the peak voltage on the coil?(work like the switched-mode power supply) on coil input should i use Transient Voltage Suppressor P6KE series(P6KE400)? or should i connect to the ground with a capacitor(33nF)?
Tomorrow i will try to connect the ignition things (ignition module, ignition coil) to a separate power supply and connect together the ground. i really hope for a positive result because i don't think what other could be.

I'm not sure if I've understood everything correctly



You know that the ETZ250 has an AC alternator with rectifier coupled behind. The Alternator has three phases, so it should be impossible to connect the regulator directly to the alternator

There is a wiring diagram

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Kleine Anleitung, wie man das Zündschloss einer RT überprüft

Didn't say that i've connected direct to the alternator(stator), D+ to D+(diode bridge)but before contact switch(to make it more reliable i've put a relay between contact switch and power consumers), D- to D-(diode bridge) and DF to the alternator rotor coil.

... to continue Ralle´s statement:

The right connections are
D+ from your voltage regulator must be connected to 61 of the rectifier help bridge matrix.
D+ from the rectifier power bridge connect to battery plus directly.

Your report does not give me a clear imagination about the state of your current electric scheme.
What does the battery say when 35V come from generator?
Where do you measure the too high voltage and what load is on when you run the engine with shortened rotor?

You use ~ for an round-about-value? That´s a little confusing because it is usually used for AC voltage.
Are the 35Volts a DC voltage or an AC between U-V resp. V-W?

Regards
Lothar

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MZ-Elektrik * Rahmennummernsammlung ES125/150 * Bulgarien 2024
Wie nennt man eigentlich Verschwörungstheoretiker, deren Theorie sich nach angemessener Zeit als richtig herausstellt?

OK sorry for confusion. the ~ is a round-about-value.
35V is DC(the measurement i've made after rectifier bridge). during the measurement i haven't any extra load, only the ignition things(ignition module, coil).
The connection i've made it is for test(D+ to D+), in the end i will connect to 61.
From the battery(YTX4-BS) i've pickup the voltage for measurement(i haven't let to run much time at high revs to not damage other electrical parts).
but it isn't peak voltage, for ex. i keep the engine revs at 5000rpm and the voltage is around 20V and it keeps it constantly.

All the behaviour seems to be a little strange ... I recommend to seperate the problem generator / ignition to get the things clearer.
If possible use an original ignition coil (about 4,5 Ohms primary) powered by an external battery for test.

Now check the generator (resistor measurment) with disassembled rectifier bridge. Although it is in German have a look at >Tabelle B.1-2< in
http://pic.mz-forum.com/lothar/ELEKTRIK/Elektrik.htm
If wire and isolation resitances are OK then do the the generator test described in chapter B.1-2
Instead of three lamps it is sufficient to use only one between U-V or V-W or W-U.

The lamp must not light - also at a high revolution number - when the 12V/21W lamp (which is powering the rotor) will be removed.
In other case the generator is wrong (without being able to explain this at the moment...)

By the way - I´ve got a sneaking suspicion that the voltage measurment by instrument could be wrong because you had only the
ignition as load. The ignition coil sends also from the primary terms heavy voltage spikes into the board net which can
produce failures especially by use of modern digital multimeters.

Regards
Lothar

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MZ-Elektrik * Rahmennummernsammlung ES125/150 * Bulgarien 2024
Wie nennt man eigentlich Verschwörungstheoretiker, deren Theorie sich nach angemessener Zeit als richtig herausstellt?

yes i use a professional digital multimeter.
Now i change the ignition module but the same coil(3.4 ohm some like that, i don't remember ) and on the voltmeter i don't get nothing it is 00.0 (it isn't the voltage to big because than it display 0L).
I've disconnected the diode bridge only the ground remain common but the same, the voltmeter indicate 00.0V
It is some old ignition coil(i get from a friend).

That´s not a question of professional or not professional but of the sensitive electronic circuits inside the multimeter.
Some multimeters are sensitive to high voltage spikes others aren´t .. it does not depend from the price, too.


Sorry, ... now the voltage is Zero or Overflow on term (61) or where ... ?

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MZ-Elektrik * Rahmennummernsammlung ES125/150 * Bulgarien 2024
Wie nennt man eigentlich Verschwörungstheoretiker, deren Theorie sich nach angemessener Zeit als richtig herausstellt?

zero on the voltmeter but the engine still running.

EDIT:
I've borrowed a analogue multimeter and the regulator is working properly! thanks
The problem is still the noise generated by ignition coil. The modules driven by microcontroller just don't work.
There is a possibility to filter it?
I will try to change the coil with my other Opel Astra(0.4 ohm) but i need to buy a 3 ohm resistor to put in array with the coil.

It is difficult. You have to put it into a complete closed metal housing. incoming, outgoing
signals and power supply must be filtered by lead-through Low-Passs-filters and/or voltage spike limited by suppressor diodes.

I am not really convinced that this will work. The series resitstors decreases the current resp. inner magnetic field
strength that means lower induction voltage .... The Opel coil is maybe designed for an other ignition method (fx capacitor ignition?)

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MZ-Elektrik * Rahmennummernsammlung ES125/150 * Bulgarien 2024
Wie nennt man eigentlich Verschwörungstheoretiker, deren Theorie sich nach angemessener Zeit als richtig herausstellt?

I had connected in array two 5.6 ohm/20W(2.8ohm) resistors, and tried out. it work wonderful, the spark is much better with this,than with the old coil and i can measure the voltage with a digital multimeter
now i'm searching after a schematic for this type of coils.