23-11-2018, 02:12 AM
Dont really understand your question.
Cant recall if dynamos have yet been yet extensively covered on the present site, so....
As diagram one end of field windings exits dynamo, the other connects to 3rd brush. (Unless someone has converted to 2 brush operation and connected the internal end directly to "earth" with the 3rd brush unconnected?)
With the brushes out of contact should be same very low resistance between adjacent commutator segments (digital meter).
To test operation, the field exit terminal and main output terminal are joined (the winter charge situation) but not to any load. Voltage to earth considerably exceeds 6. Must not be permanently operated in this state with the field linked but no battery load.
(In practice in car, the 3rd brush is usually some distance from the earth brush if ammeter ouput is not to exceed 8-10 amps, lights off. Operated as two brush currents would be excessive)
Cant recall if dynamos have yet been yet extensively covered on the present site, so....
As diagram one end of field windings exits dynamo, the other connects to 3rd brush. (Unless someone has converted to 2 brush operation and connected the internal end directly to "earth" with the 3rd brush unconnected?)
With the brushes out of contact should be same very low resistance between adjacent commutator segments (digital meter).
To test operation, the field exit terminal and main output terminal are joined (the winter charge situation) but not to any load. Voltage to earth considerably exceeds 6. Must not be permanently operated in this state with the field linked but no battery load.
(In practice in car, the 3rd brush is usually some distance from the earth brush if ammeter ouput is not to exceed 8-10 amps, lights off. Operated as two brush currents would be excessive)