Well it starts, BUT....

Maestro, SEI-V

Re: Well it starts, BUT....

Postby penman » 09 Feb 2017 09:59

I am still attracted by this idea. Does anyone have information on the number of turns needed on the 5 coils for this modification? I have searched this forum and I've also looked on the Dutch website. The latter does give information on rewinding to the original spec, but not for this upgrade. I'm guessing it'll need about 40 to 50 turns of thicker wire, say about 1mm on the tall coils and 20 to 30 turns on the short coils, but in the absence of any guidance, I'd have to do some tests to verify that.

Having got the wire to simply rewind the original coil, I'll probably do that in the interest of getting the bike on the road quickly, but I would like to pursue this upgrade as another project for the future - especially if the regulator isn't working, it may be sooner than later!

If anyone out there has a spare stator for sale, a scrap one would be fine, do let me know!

Regards to all,
Joe.
1985 Morini 350 K2
1978 Triumph T140 E Bonneville
1975 Triumph T160 Trident
2014 BMW F800GT
1978 Morini 500
penman
 
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Re: Well it starts, BUT....

Postby EVguru » 09 Feb 2017 13:04

No need to do any re-winding.

The half wave rectifier uses two windings connected in series, with the red wire being the centre tap where the two coils join. Seperate the two windings (abandoning the red wire) and connect them in parallel instead of series.

Make sure the polarities are correct or you'll get no voltage.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
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Re: Well it starts, BUT....

Postby penman » 09 Feb 2017 15:58

EVguru wrote:No need to do any re-winding.

The half wave rectifier uses two windings connected in series, with the red wire being the centre tap where the two coils join. Seperate the two windings (abandoning the red wire) and connect them in parallel instead of series.

Make sure the polarities are correct or you'll get no voltage.


Thank you Paul, you are absolutely correct (why didn't I think of that?). I need to trace out the coil interconnections again to be sure of the phase relationship between the two yellows, but I am pretty sure they are out of phase, so the link at the red would need to be broken and two new links put in to parallel the windings. So, I'll rewind the damaged coil and see how it works connected as standard. If there's a problem with the regulator, I'll re-connect it for a "modern" regulator, I may even have one in my stash.

One remaining puzzle is that when I originally checked this alternator, there was zero output from either winding and both measured open circuit. Now I can only find one break and the other winding measures OK, but I suspect there is another break which I have disturbed so that it's making contact again. If so, it'll soon fail when I try to use it!
1985 Morini 350 K2
1978 Triumph T140 E Bonneville
1975 Triumph T160 Trident
2014 BMW F800GT
1978 Morini 500
penman
 
Posts: 278
Joined: 08 Mar 2016 09:20
Location: Milton Keynes

Re: Well it starts, BUT....

Postby harrymuffin » 09 Feb 2017 16:20

I have a late 500 1984 with the red wire and it is rated at 140w but can see 18amps once started by motor and with the lights on, the other 500+ also has the same stator using the screw on lid regulator which again for testing purposes also has an 18A output. I also have a spare stator with no red wire and that on testing also gave a max of 18A with both latest and screw on regulators (tested on a K2). All this was done some time ago - last century - when seeing which was best so that I could run illegal 100w headlamp bulbs on my everyday bike at the time was the K2.
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Re: Well it starts, BUT....

Postby penman » 09 Feb 2017 18:48

18A surprises me, that's well over 200W - and I shall be more than happy if that's what these alternators can give! If this wire ever arrives, I'll do the rewind, do some tests and post the measurements here. Of course I don't know how good the rotor magnets are. I'm a bit more familiar with the Lucas 3 phase alternators from the mid to late '70s and those can give around 13A at 3000+ rpm - and I thought that was pretty good. Hmm, 18A eh? feeling more enthusiastic already!
1985 Morini 350 K2
1978 Triumph T140 E Bonneville
1975 Triumph T160 Trident
2014 BMW F800GT
1978 Morini 500
penman
 
Posts: 278
Joined: 08 Mar 2016 09:20
Location: Milton Keynes

Re: Well it starts, BUT....

Postby harrymuffin » 10 Feb 2017 10:31

This was at 6000rpm where maximum output is and gave this output for around 30-45secs before dropping back having charged the battery after using the starter motor. The generator easily balanced the 100watt headlamp and rear lamp. I think the none red generators are rated at 160watts. I assumed the latest regulators (then that is) were rated at 18A and the earlier screw together ones rated at 12A but I found that both gave the same output. I don't suppose they would last long at the full output but I have only had one regulator fail and that was on a K2. I do not run with headlamps or lights on during the day only when I can't see where I am going but never had stater motor problems the next morning owing to low battery charge.
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Re: Well it starts, BUT....

Postby penman » 12 Feb 2017 16:17

Well I rewound the stator and it works fine. However the regulator doesn't regulate and I stopped the engine when the battery voltage reached 15.8v. That's an almost new Motobatt battery which I pinched from my Trident and I would like to have a bit more life out of it! I'll give it some thought, but I'll probably order a normal single phase regulator from Paul Goff and parallel the two stator windings as Paul C suggested.

Unless I can repair the regulator. It is the earlier type with a removable cover - does anyone know if you can access the components, or is it all potted? And does anyone know if there's an accurate circuit diagram anywhere? I'll think about this, after the effort of rewinding the stator, I do like the idea of repairing the regulator.

The good news is that this is just about the easiest starting engine I've ever encountered, despite the very cold weather. I't just bursts into life, most gratifying!

Joe.
1985 Morini 350 K2
1978 Triumph T140 E Bonneville
1975 Triumph T160 Trident
2014 BMW F800GT
1978 Morini 500
penman
 
Posts: 278
Joined: 08 Mar 2016 09:20
Location: Milton Keynes

Re: Well it starts, BUT....

Postby harrymuffin » 13 Feb 2017 18:47

I have wiring diagrams for all the Morinis on A3 coloured laminated sheets which makes life much easier than the diagrams found in the booklets. I have two diagrams for the 500's on with the red wire and one without. I also have two 500 bikes one with the cast aluminium regulator and one with the early take it apart one. As you have the red wired alternator then have you got a brown wire that connects the switchboard to the brown on the regulator? The red wire should go up to the switchboard. Owing to the size of the diagrams I cannot scan the whole into the computer but if you PM me then I will send you those bits of the wiring that include the switchboard.
Incidently, these drawings I down loaded from the internet but have no idea from where but I think they are of Australian origin. If anyone wants copies of these wiring diagrams I am quite happy to arrange for copies to be made and laminated or not, they make interpretation so simple as all the wires are coloured. I have early and late 500's, 350 with the 6 pole indication switch, 350 with 5 pole ignition switch with the electric tacho. There used to be a do it yourself circuit board with picture in one of the magazines that I have already mentioned before and if you go to the Dutch clubs website I think there is also a make your own regulator in the technical section. I believe it is possible to use a Harley Havidson regulator as I did have one until recently, it had two inputs and one output, did not have to resort to it as I keep a spare.
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Re: Well it starts, BUT....

Postby penman » 13 Feb 2017 21:52

Many thanks for that Harry, it's the circuit diagram for the regulator itself I was looking for, but now I have taken the lid off the regulator and the components are potted in some kind of black resin. You can access the two thyristors which seem to be OK, but you can't even see the other components. I did some more tests on it today and it just appears to be unregulated, or trying to regulate at too high a voltage.

I did some current measurements. I deliberately discharged the battery a bit and then watched the current and voltage. The highest current I measured was just over 9A, at about 12.6v. As the battery voltage rose, the current fell to about 8A. I connected a few bulbs to the battery until i brought the voltage down to about 14.5v, at which point it was charging at about 8.5A. This was at about 5000rpm. In fact the absolute max is at about 6000rpm, though you don't get much more beyond 4000. At idle, there is practically no charge, less than 0.5A. Now I was getting interested in all this, I pulled the 1978 Bonneville out, which has a Lucas 3 phase alternator. This hits its max at about 3000rpm, when it makes about 13.5A. The big difference is at idle, where it still makes about 4A. No wonder they all moved to 3 phase in the '80s. Still, the Morini alternator should be quite adequate - once it's working properly.

I had a look on ebay, which has produced one of the newer style regulators for €29 - I took a chance on that, it's coming from Austria, so I expect I'll have a few days wait. If this solves my problem, great - if not it's over to plan B, a bit of rewiring and a new regulator.

By the way, a lot of info on this subject on the Dutch website and via link from there to a German website. Thankfully my son's a German teacher, I just knew he'd be useful some day!
1985 Morini 350 K2
1978 Triumph T140 E Bonneville
1975 Triumph T160 Trident
2014 BMW F800GT
1978 Morini 500
penman
 
Posts: 278
Joined: 08 Mar 2016 09:20
Location: Milton Keynes

Re: Well it starts, BUT....

Postby EVguru » 13 Feb 2017 22:24

penman wrote:Many thanks for that Harry, it's the circuit diagram for the regulator itself I was looking for,!


It's on the Dutch site.

The Morini regulator works differently to most. It's not a shunt regulator dumping excess energy as heat, it's a controlled rectifier.

It needs to see a switched ignition feed to sense battery voltage and turn on. I won't charge a battery under about 10v because it could have a shorted cell.

If the voltage on the sense terminal is wrong due to a bad connection or poor earth, then the regulation voltage will be wrong too.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
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Re: Well it starts, BUT....

Postby penman » 14 Feb 2017 09:37

The diagram on the Dutch site is for the later type regulator, which seems to be quite different. There are some photos of the earlier regulator (like mine) but no diagram. On the German site there is a circuit diagram for (I think) an updated version of the earlier regulator, a very simple design, again using a pair of SCRs. One option would be to build the "German design" on a bit of veroboard, which could probably be made to fit in the existing case.

I take your point regarding the switched supply to the regulator, but it's OK, one of the first things I checked (ever hopeful of a simple fault!). I've high hopes for the later style regulator I have coming from eBay, fingers crossed. But if that turns out to be faulty I'll admit defeat and go for a modern series regulator, they're cheap as chips and if my experience is anything to go by, they are very reliable. It would mean re-doing the interconnections on the alternator coils to get the two strings in phase, but that should be simple enough.

By the way, do my current measurements sound typical to you? They indicate a max output of about 120W - perhaps a bit less at normal cruising speed. That should be plenty, given that it doesn't have to supply the ignition, and a 60W headlamp should be no problem at all.

I must say, I'm impressed with this Morini regulator from the 1970s, a proper electronic series regulator from the days when Lucas just whacked a massive zener across the battery - maybe that was cheap and effective, but what a crude and wasteful system! It offends one's engineering sensibilities!
1985 Morini 350 K2
1978 Triumph T140 E Bonneville
1975 Triumph T160 Trident
2014 BMW F800GT
1978 Morini 500
penman
 
Posts: 278
Joined: 08 Mar 2016 09:20
Location: Milton Keynes

Re: Well it starts, BUT....

Postby penman » 14 Feb 2017 11:10

Hi all,
For the benefit of anyone else who has to go down this path, here is the diagram from the German website, http://www.italoclassicbikes.de/ He seems to have designed a pcb for this circuit, but no details are given. There is more technical info, but of course it's in German.

Image

The two connections labelled "Lima-ge" go to the two yellow wires from the stator and also to the two thyristor cathodes, the anodes going to earth. At a casual glance, it's easy to mistake this for a shunt regulator, in fact it's a series regulator with the switching on the negative side. It took me a little while to get my brain around this, everything being "upside down"!

The switched supply goes to "P1" and the centre tap of the stator windings goes to battery positive. I'm not sure why R1 and R3 are in parallel, unless it allows a bit of fine tuning.

I don't know if this is a copy of the original regulator, or if it's been modified in any way. Looking at it again, it's tempting to rebuild it.

Joe.
1985 Morini 350 K2
1978 Triumph T140 E Bonneville
1975 Triumph T160 Trident
2014 BMW F800GT
1978 Morini 500
penman
 
Posts: 278
Joined: 08 Mar 2016 09:20
Location: Milton Keynes

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