10-06-2019, 08:46 PM
To rewind an armature for 12v requires thinner wire and as overheating of the armature is the main problem this is self defeating. (It was common to rewind troublesome armatures with a thicker gauge but which delayed cut in )
Most dynamos I have seen have commutators too worn to warrant rewire. Do the reconditioners of Seven dynamos have a source of new comms?
I have to concede that modern sealed batteries are not suited to the original Seven charging. Do not like more than about 14.4/7.2 volts. The car system kept at a low rate except at night and maintained by a modern bench charger seems more ideal.
The idea of introducing electronics to a Seven troubles me, but I suppose if operating 2 wire, if the electronic regulators can limit max 2 wire field current mainly by switching, an earlier cut in is possible than otherwise. The switched field current has an exaggerated heating effect but the fields seem very tolerant.
Most dynamos I have seen have commutators too worn to warrant rewire. Do the reconditioners of Seven dynamos have a source of new comms?
I have to concede that modern sealed batteries are not suited to the original Seven charging. Do not like more than about 14.4/7.2 volts. The car system kept at a low rate except at night and maintained by a modern bench charger seems more ideal.
The idea of introducing electronics to a Seven troubles me, but I suppose if operating 2 wire, if the electronic regulators can limit max 2 wire field current mainly by switching, an earlier cut in is possible than otherwise. The switched field current has an exaggerated heating effect but the fields seem very tolerant.