dynamo polarising

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dudley472
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Location: wolverhampton

dynamo polarising

Unread post by dudley472 » Wed Mar 11, 2009 9:56 am

i need to sort the electrics on my 1930 bsa sloper, the dynamo has the voltage regulator built in, do i polarise in the same way ?? cheers

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DAM
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Location: North Cornwall

Re: dynamo polarising

Unread post by DAM » Wed Mar 11, 2009 6:52 pm

To polarize the 3 brush dynamo with internal regulator -
Run engine slowly, put switch in the charge position and momentarily press the cutout contacts together.

Or if the dynamo is off the bike -
Link the shunt field terminal to the dynamo body and flash the battery to the output brush carrier (the one furthest away from the 3rd brush).

dudley472
Posts: 219
Joined: Wed Feb 18, 2009 9:22 pm
Location: wolverhampton

Re: dynamo polarising

Unread post by dudley472 » Wed Mar 11, 2009 8:05 pm

right thanks for that, this leads to another question.........where is the charge switch?? headlamp perhaps?? although the bike has been restored the loom has not and is pretty much non existant, in think a wiring diagram is in order, also if it is part of the light switch the i have is non standard... cheers

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DAM
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Location: North Cornwall

Re: dynamo polarising

Unread post by DAM » Wed Mar 11, 2009 8:27 pm

The charge switch is built into the light switch, it adds a resistor in series with the dynamo field coil to halve the charge rate when the lights are off.
I'll scan the lucas magdyno wiring diagram for you.

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DAM
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Location: North Cornwall

Re: dynamo polarising

Unread post by DAM » Wed Mar 11, 2009 8:50 pm

Lucas 3 brush dynamo wiring diagram

http://www.bude-electrician.co.uk/pdf/l ... wiring.pdf" target="_blank

Diagram is a bit marked, but the books it came out of were taken on HMS Londonderry, Red Sea Patrol in 1935 by the gentleman that I bought them from.

dudley472
Posts: 219
Joined: Wed Feb 18, 2009 9:22 pm
Location: wolverhampton

Re: dynamo polarising

Unread post by dudley472 » Thu Mar 12, 2009 12:33 am

thank you very much, i love the internet

The Mighty Gusset

Re: dynamo polarising

Unread post by The Mighty Gusset » Thu Mar 12, 2009 1:19 am

dudley472 wrote:I love the internet
I don't, it's just full of dirty pictures !

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