Re: [CAD_CAM_EDM_DRO] DC feedback motor

> Hi,
>
> Is a DC feedback motor with 5 plus 2 wires the same as a servo motor?
>
> The 2 wires is for the quadrature rotary encoder?
>

Peter,

A quadrature encoder should have at least 4 wires of its own, as it
needs its own power and ground. Some may have as many as eight wires
- sending quadrature plus an index differentially, plus 2 lines for
the power supply.

A feedback device having 2 wires is more likely a DC tachometer -
basically a small DC generator which produces a voltage proportional
to the motor speed. Many servo amps - especially older ones - need
this signal in addition to the encoder signals needed to close the
position loop.

As for the 5 wires going to the motor - sounds like this may be a
brushless motor, or have a wound field, or something...

You probably can use it as a servo motor - you just may need to add an
additional feedback mechanism, find a compatible amplifier, and of
course decide if the motor characteristics are suitable to your application.

Or is it 5 wires to the encoder and 2 wires for the motor??? That
could be a simple permanent magnet DC brush motor, with a quadrate +
index encoder.

Chris

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
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