Norton Dominator 99 problems

A 13 V Zener diode will not full charge battery. Optimum voltage should be 13.8 to 14.2.

With a magneto, you may get by with 13 V, but what is your reason for doing it?

Slick

Hello,

I did the rectifier/regulator and it works. Its charging battery and somehow it is charging alot over 13V higher revs, up to 15V actually.

I just wanted to try this thing out and it seems to work fine, parts cost only about 12,5£.

Im wondering why it is charging over 13V, even with all lights on. Maybe the zener is soldered wrong way?

EDIT: The zener has to be right way soldered, otherwise it would not work at all. Its interesting why its charging 14,5-15V with higher revs, even when lights are on.

And this was just an test for me, i still have ordered single phase 200w rectirier/regulator that im going to use. But next time i come up with broken rec/reg i might just make it my own. That diode bridge should have ridiculous capacity of watts, with P=U*I its 35000watts (35amps, 1000v), so with my 120watt alternator im using less than 0,5% of its capability. Which would be "good" kind of because its not producing heat so much.

Edit 2: Well i changed the zener diode other way, now lights off i can get it no more than about 13V. Something like 12,9-12,95V. But now it wont get higher than 12,2V with lights on.

Hello,

Luckily i bought more than one zener diode, the first one seemed to be faulty one. Another zener fitted the way i think is right its not gettin over 13V lights off. And when lights are on its not getting over 12,20V.. its no matter which way the working zener is, same result. With the first zener diode "right" way assembled it gave upto 15V and "wrong" way only 13V.

Could the zener diode just be to small?

The zener is working propely since system voltage is not getting higher than 13V. But there is maybe something else wrong since alternator cannot keep the voltage at 13V when lights are on.

But, when i had the faulty zener diode fitted, it was charging lights on 13V at idle, and without lights on with revs climbed up to 15V.

Lights ON at higher revs it was somewhere 14,5-14,7V.

I need to check diodes to be sure they are still good and maybe i'll try to attach the rec/reg straight to the light circuit without battery to see if i still have same symptoms than i had with the boyer power box. (Symptoms were that the system voltage dropped to 3,5-4Vdc when main light bulb was on)

Hello,

I am still trying to come up with better solution to the key switch.

I was wondering if there would be DPDT key switch that would be 0-1 position and other link is NC(Normal close) and other is NO(Normal open)

For example when the keyswitch would be OFF, 1-2 terminals would be together (NC) and terminals 3-4 would be open (NO). When key switch is turned ON-position terminals 1-2 would be open and 3-4 would be closed.

Well, i resoldered the first Rec/Reg and when i was testing it out for shorts, i made mistake myself. I managed to short it accidentally and one diode inside the rectifier blew, so the rectifier is faulty now. Whole setup flew to trashcan.

But i wont give up. I was wondering why it would need to be so "complicated" with all those triacs, zeners and resistors, so i drawed new schematic lot more "simple" as the first one.
Here it is. Its just 35A 1000V diode brigde as rectifier that converts AC input to unregulated DC output.

Unregulated DC output goes to 13,7V voltage regulator which regulates DC current to 13,7V, also there is 2 pcs 1000µF capacitors helping to smooth the current. (Capacitors arent necessary since we are going to use battery).

I think this kind of setup would work with single phase alternators, probably could suit 3-phase with some changes aswell.

I have ordered those components which should come either tomorrow or friday. Also ordered nice aluminium heat sink, where i am going to attach those components and wire them. If tests are great success, then it will be casted with epoxy addhesive.

If someone still is wondering why am i doing this, im not completely sure either. But i am considering this as my hobby, and i like trying to fix stuff myself and not just get new part and replace it. This keeps my "hobby" more interesting. When i fail enough times, then i'll give up and go the easiest way around and replace it with new item.

I havent still managed to get suitable rec/reg here in Finland, the one that they offered me at the spares shop was only an regulator, i need both rectifier and regulator. I'll visit the shop one more time to see if they can order rec/reg from somewhere.

I know there is lot of rec/regs out there and even in here Finland, but there is no any specs given with them so i dont know how many watts either one can take(even if i ask about it, the seller cannot tell for sure) and i dont want to buy one after another just to see if it brakes or not. Building my own out of seperate components is WAY much cheaper and worth a shot to try out at this point.

Hwllo,

I got the parts today and it seems like i need to change the polarity to negative.

Since im running magneto do i need to do any changes? I tested the light circuit with 12v battery negative ground and positive to the wire and lights were working normally as i suspected.

Im only wondering if the magneto bothers about this change in any case? Does it matter which polarity it is when you use cut-off to shut engine down?

The thing that the voltage regulator uses its body as ground also, so when i bolt it to the heat sink it the sink has negative polarity and when rec/reg is attached to the frame its no good.

It would be possible to insulate voltage regulator, but its tricky and i see its easier to change ground polarity.

You may be enjoying yourself, but the lack of basic information is very much complicating your getting to a solution.
Here is a normal lucas zener performance curve:
http://atlanticgreen.com/images/zener.gif
Normal good battery is 12.8v. The normal zener beginning is 14.3V.
You can easily see why you can get well over 15 volts with a zener and still be functional and normal (with no battery in the system).
FWIW that is only sinking 33.75 watts from a typical 120watt charging system at 15v .
With an early bike you have a two stage charging system, a lower current part and the higher headlight part. IIRC together they make up 120W total.

Polarity of your battery, charging system and lights has no effect on the magneto at all.

Hello,

Yes, i am not professional with electrics, but my co-worker has helped me out with this pretty much.

Never mind the polarity, im gonna stick with the positive ground, and gonna get heat sink insulator so i can insulate voltage regulator.

The spare parts shop where i went earlier did not have possibilities to order correct rec/reg before winter.

I hope that with the help of my co-worker i can make reliable and working rec/reg.

dynodave said:

You may be enjoying yourself, but the lack of basic information is very much complicating your getting to a solution.
Here is a normal lucas zener performance curve:
http://atlanticgreen.com/images/zener.gif
Normal good battery is 12.8v. The normal zener beginning is 14.3V.
You can easily see why you can get well over 15 volts with a zener and still be functional and normal (with no battery in the system).
FWIW that is only sinking 33.75 watts from a typical 120watt charging system at 15v .
With an early bike you have a two stage charging system, a lower current part and the higher headlight part. IIRC together they make up 120W total.

Click to expand...

The thing with the zener was that it was 13V zener which in my understanding should not let charging circuit get much higher than 13V, but was still highest around 15V. When i replaced the zener with new one, the system did have only max. 13V voltage.

The components were not exactly the same as was first listed, instead of UNL2003A and BTA26- i had UNL2004 and BTA41, because they were closest available at the moment. After first tests i disasembled it, and resoldered using mmj wire core and when i was testing UNL and triac i noticed that the triac was faulty one, soon after i accidentally shorted the circuit and it broke rectifiers diode also, so it went to trashcan.

Tomorrow i will get those heat sink insulators, so i can build this second "prototype" and i will also test it tomorrow. Since i have started to talk about all this homemade rec/reg stuff, i'll keep reporting here the results, in case someone finds this even little bit interesting to follow and wants to know how it came up in the end.

If someone wants, i can also take pics of differend phases.

13 volts is too low.

Someone already said that.

Re;” If someone still is wondering why am i doing this, im not completely sure either. But i am considering this as my hobby, and i like trying to fix stuff myself and not just get new part and replace it. This keeps my "hobby" more interesting. When i fail enough times, then i'll give up and go the easiest way around and replace it with new item.”

I think I am right that the 99 originally had the 6 volt alternator that could be changed to 12 volts once Lucas had found/designed a way of using a Zener with a heat sink. You don’t appear to have listed what alternator you have; there are different Zener diodes available out there for different alternators.
Most cut out between 14.3-14.7volts which is pretty strict criteria, a low voltage like 13 volts either is a dirty connector, black copper core wires, or a fault in the alternator, usually the first or second.

Bernhard said:

You don’t appear to have listed what alternator you have;

Click to expand...

He has;

norton-dominator-problems-t27317-60.html#p361888

KuusistoNorton said:

Yes it seems to be RM21, its Lucas 47205, 12volt alternator.

Click to expand...

Hello,

Well the test was not good, dont know why but the voltage regulator blew into peaces almost immediately after starting the bike.

At idle it did not charge at all, but when i started to rev it little bit i saw voltage rising, but once it got 13,5V the regulator popped in to peaces.

I am not completely sure why it happened, there should not be even close to 40Vdc input from the rectifier. Not sure how much amps the regulator can hold but i would say it either got too much amps, or the regulator was faulty one. All the wirings were propely made and there was no shorts.

Not sure if i will try it once more with new voltage regulator, but at the moment i feel little bit upset and would just like to get over with this allready.

RGM sells 12volt rec/reg for 19£, but when i order it to Finland the total cost is 44£. Not nice.
Heres pic of the regulator.

There are cheap regulators on Ebay.

They may not be built to space travel standards, but they don't instantly blow holes in themselves.

Triton Thrasher said:

There are cheap regulators on Ebay.

They may not be built to space travel standards, but they don't instantly blow holes in themselves.

Click to expand...

Thanks, i need to check it out.

I'll need to get rid of this problem, even if it would cost little bit more than i would like to, but so many good riding days missed because of this rec/reg problem.

KuusistoNorton said:

…RGM sells 12volt rec/reg for 19£, but when i order it to Finland the total cost is 44£. Not nice.

Click to expand...

Theirs shipping quotes to foreign countries are extremely high :cry: That's the reason why I don't order there any more.

Fritz

Your Pb137 regulator is rated at 1.5 amps which is why it exploded. It's designed for low output battery chargers.

Ian

Nortoniggy said:

Your Pb137 regulator is rated at 1.5 amps which is why it exploded. It's designed for low output battery chargers.
Ian

Click to expand...

Well it appears you are using cheapo components in your home made reg/rec –they simply are not up to the job, you can bet your shirt that the superior parts in the Lucas reg/rec were ordered in bulk and therefore cheaper than you can buy them at- me thinks you may have to bite the bullet and obtain the genuine article, are there not any bike breakers in Finland :?:
You are not restricted to getting one off a Norton as BSA Triumph and others also used the same components.