[Milsurplus] Help with Bendix Dynamotor

[Mike Hanz]

Robert Flory wrote:

>I'm new to messing with dynamotors, so I want to avoid any rookie mistakes.
>I have a Bendix DA-1F that seems to have a separate field coil.  I'm
>wondering if that wants to have a rheostat in series with it to adjust the
>output level, and if I am going to get in trouble by running full juice to
>it.  The field coil measures 24 ohms, so it would have an amp running
>through it at full voltage.
>

That's normal, Rob.  The field coil is shunt connected across the L.V. 
commutator brushes, and thence to 24 vdc.  They are all configured 
pretty much the same way, at least in my experience.  You can certainly 
lower the current with a rheostat in series with the field coil, but 
remember that in a dynamotor the field coil simultaneously provides the 
field for the generator section.  Decreasing the field current very much 
starts giving you stability problems and poor voltage regulation.

73,
Mike