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Re: More dynamo issues.

Posted: Mon Aug 27, 2018 4:47 pm
by alan.moore
Bill, how do you check this resister i.w where are the wires at each end?

Re: More dynamo issues.

Posted: Tue Aug 28, 2018 7:20 am
by Phil B
Sorry for not updating, currently on a snap break up in the North Pennines. Normal service resumes on Saturday. Itching to get on with it!!

Re: More dynamo issues.

Posted: Tue Aug 28, 2018 3:13 pm
by bill.bottrill
SAM_1019.JPG
Alan
This photo shows you the resistor,sorry I can't put arrows on etc.
Can you see it's the round black jobby,to check it you need the fade plug out.one meter probe on the frame (ie V) and the other meter probe on the copper clip or the flat strip attached to it.can you see the points or contacts worked from the coil in the forground you need to put a sheet of paper between them or you won't get a reading
I would advise you disconnect the battery earth if you are poking around on the bike as even though it's a small battery a short can fry the wiring!

Perhaps we can demystify a bit of this control box,everybody knows to join F to D on the dynamo to check if it's charging, but look, that's all that is happening inside this bit of the mcr2
The F and D wires come straight from the dynamo to the control box plug (F) a(D) e. you can see (F) (bottom rh side) on the photo and the bit of soldered wire that curls around to an insulated screw on the back of the frame(V) this screw holds one of the contacts of the points on the other side of the frame(V) all insulated from the frame(V)
The other half of the contacts is attached to the movable arm of the coil which in turn is attached to the frame (V) through a bendy flat spring,the two screws on top of the frame (almost there!) the frame(V) is directly attached to (D)
So at rest the contacts are closed so it's just doing the same as joining (F)to(D)
Also the resistor can now be seen to be straddling the contacts from the insulated screw along the flat wire through the resistor and down to the frame (V) the frame is on an insulated panel so it doesn't short to the fixing bolts etc.

Re: More dynamo issues.

Posted: Tue Aug 28, 2018 5:06 pm
by bill.bottrill
Sorry I've hi-jacked your thread, I should have put the above and the previous post under keith's dynamo problem bill

Re: More dynamo issues.

Posted: Tue Aug 28, 2018 9:47 pm
by Phil B
Absolutely no problem Bill. All info is useful and now you’ve posted, people can search for your posts.

Re: More dynamo issues.

Posted: Tue Aug 28, 2018 10:59 pm
by nevhunter
Joining F to D won't apply any power to provide the initial magnetism.. The cutout points are apart. If you close them manually sometimes they arc together F to D will eliminate the cutout-regulator when testing the generator by itself. Don't run it at high revs as the voltage can go quite high. Nev