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Polarising a Dynamo
The last thing you'll need to do to is to polarise the dynamo field coils for positive or negative earth to suit your application.
This applies to ALL cars and some motorcycles.
Electronic regulators are availabe either in positive or negative earth versions.
***Remember, with negative earth you can run all sorts of more modern equipment via your cigar lighter with any age of car or bike***
If your motorcycle is 12v or you've upgraded from 6v to 12v then with a negative earth regulator you can install a hidden cigarette lighter socket. With this you can charge your mobile phone on the road or even run a Sat Nav on your classic. Handy for powering that electric pump to inflate your airbed when camping too......
Worth thinking about before you order a regulator.
To polarize a Lucas dynamo for NEGATIVE earth
(shunt field)
Your battery's NEGATIVE terminal should be connected to the chassis or frame.
Disconnect the D & F wires from the dynamo. Run a wire from the unearthed terminal on the battery (i.e. positive) and "flash" it onto the F terminal on the dynamo. By flash I mean brush it over the F terminal 2 or 3 times until a small blue spark can be seen.
Your dynamo's field is now polarised for negative earth and ready to safely connect to an electronic regulator
To polarize for POSITIVE earth
Your battery's POSITIVE terminal should be connected to the chassis or frame.
Disconnect the D & F wires from the dynamo. Run a wire from the unearthed terminal on the battery (NEGATIVE) and "flash" it onto the F terminal on the dynamo. By flash I mean brush it over the F terminal 2 or 3 times until a small blue spark can be seen.
Your dynamo's field is now polarised for positive earth and ready to safely connect to an electronic regulator
To polarize a Bosch or other series field dynamo for negative earth
Disconnect the wires from the dynamo. Run a wire from the earthed (negative) terminal of the battery and hold it onto the DF terminal on the dynamo. Run another wire from the positive terminal of the battery and "flash" it onto the D+/61 terminal on the dynamo until a small blue spark can be seen.
The dynamos field is now polarized for negative earth and ready to safely connect to an electronic regulator.
ALL ELECTRONIC REGULATORS
ARE POLARITY SENSITIVE!!!
FOR THIS REASON IT IS IMPORTANT TO MAKE SURE YOUR DYNAMO IS CORRECTLY POLARIZED. THE REGULATOR COULD BE DAMAGED IF IT IS NOT
UNDER NO CIRCUMSTANCES CONNECT AN ELECTRONIC REGULATOR TO ANY DYNAMO WITHOUT POLARIZING IT CORRECTLY FIRST.
THE SMALLEST REGULATOR (FOR MOTORCYCLES) IS AVAILABLE AS A POSITIVE EARTH UNIT AS WELL AS A NEGATIVE EARTH UNIT. ONLY WITH THE POSITIVE EARTH VERSION DO YOU POLARIZE YOUR DYNAMO FOR POSITIVE EARTH.
I CAN'T STRESS THIS ENOUGH.
IF IN DOUBT???
LET ME POLARISE YOUR DYNAMO AND FIT YOUR NEW ELECTRONIC REGULATOR FOR YOU.
IF CORRECTLY FITTED, AN ELECTRONIC REGULATOR IS A
FIT AND FORGET MAINTENANCE FREE UNIT