24-04-2020, 11:47 PM
(This post was last modified: 24-04-2020, 11:50 PM by Tony Press.)
(24-04-2020, 09:16 AM)Bela Wrote: @Tony Press
Thank you for that documents which help to understand. But a question remains.
If the dynamo shall generate 12V - does it works with only a 12V battery or does it need an additional 12V cut out?
Not sure what you mean here- The Austin 7 always had a 6 volt system and I have always kept with this- messing about with a 12 volt conversion has never appealed - keeping it original is most of the enjoyment of a vintage car.
Of course the Austin 7 has a manual system of regulation. With a magneto engine and Lucas SM3 panel, this is achieved by turning the dynamo on or off .
The later SM5 panel with the Lucas/CAV dynamo had a field resistor built into the four pole winding with the switch having a full (winter) charge and half (summer) charge switch.
From the pictures of your special the dynamo appears to be this Lucas/CAV dynamo.
The later Austin 7 Dynamos had external resistors providing the same service.