re:
"If a full wave bridge rectifier were connected between the supply
connections & the permanent magnet motor, the supply polarity could be
connected to the motor either way & it would still run in the same
direction"
Don't think so. Rectifiers (diodes, usually arranged as half- or
full-wave bridges) are used to convert AC current into a "lumpy"
DC current, which is usually smoothed with capacitors. A full-wave
bridge rectifier on a DC current (Healey "power supply") would just
pass the current (to only one of its outputs).
bs
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Bob Spidell San Jose, CA bspidell@comcast.net
'67 Austin-Healey 3000 '56 Austin-Healey 100M
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> Hi Earl,
>
> Most older DC blower motors were built with series connected armature &
> field windings. They will rotate in the same direction regardless of
> which way the power is connected. These motors "can" be reversed by
> INTERNALLY reversing the connections of the field or of the armature but
> not both.
>
> Some newer motors have permanent magnets in place of the field windings.
> This type of motor will run backward if the supply connections are
> reversed.
>
> If a full wave bridge rectifier were connected between the supply
> connections & the permanent magnet motor, the supply polarity could be
> connected to the motor either way & it would still run in the same
> direction - As Jim H. says.
>
> To my knowledge, all Healey blower motors were of the first type. Not to
> say that the "reversing motor" in question has not been changed to a
> permanent magnet type somewhere along the way. Either that or your
> theory about blockage may be correct.
>
> Certainly an interesting thread.
>
> Dave Russell
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