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Control Box Connections [Lucas RB106/2]
- Thread starter cdwatson
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Roger
Luke Skywalker
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To stop your dynamo burning itself out when the battery is very discharged.
I was going to try to explain, but I found https://www.sabra.be/GB/Tecnics/RB106.htm which does it a lot better than I could!
I was going to try to explain, but I found https://www.sabra.be/GB/Tecnics/RB106.htm which does it a lot better than I could!
5
57_BN4
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The best understanding I have is the regulator is designed so a flat battery won't dim the lights at night because the system voltage is controlled separately in response to loads on the A and A1 terminals.
The A and A1 terminals are separated by only a few extra turns of thick wire on the regulator bobbin. The battery charges via the A terminal which has less turns than the A1, therefore if the battery is flat and draws a high current, it doesn't 'pull' (magnetically) as much on the regulator points as a high current to the vehicle loads would. Pulling the regulator points open cuts field coil current and therefore regulates generator output.
The sum of the current in the two windings matches the total capacity of the generator to prevent overload but the different number of turns between them allows for a higher regulation voltage than otherwise would occur if the (flat) battery and loads were on the same terminal.
If you never drive at night with a flat battery then the two terminals perform the same function.
Andy.
The A and A1 terminals are separated by only a few extra turns of thick wire on the regulator bobbin. The battery charges via the A terminal which has less turns than the A1, therefore if the battery is flat and draws a high current, it doesn't 'pull' (magnetically) as much on the regulator points as a high current to the vehicle loads would. Pulling the regulator points open cuts field coil current and therefore regulates generator output.
The sum of the current in the two windings matches the total capacity of the generator to prevent overload but the different number of turns between them allows for a higher regulation voltage than otherwise would occur if the (flat) battery and loads were on the same terminal.
If you never drive at night with a flat battery then the two terminals perform the same function.
Andy.