Re: [CAD_CAM_EDM_DRO]

Steve, et. al.

Now that you have made the fatal error of showing some knowledge of DC
motors my next victim is obvious.

Some time back, I also made the error of thinking a DC motor is a DC motor,
is a DC motor...... and bought three big ones. They are about 5 inch dia x
11 inches long with 5/8 shafts out each end. One bare back end, one looks
like it has an encoder and one has something else (only 2 wires) Square
flange mount.

The things have a pair of brushes on each end. Each pair of brushes is
serviced by 2 wires approx 16 gage.
The data plate says 220 VDC .4 A (400MA) 2200 RPM

12VDC will run the motors through either set of brushes alone.

12 VDC willl run the motors much faster if the brushes are connected in
series.

12 VDC will make the motor jump up and down if you wire the brushes in
series the wrong way.

They produce a lot of voltage when turned by hand.

Photos and additional info cheerfully furnished if it will assist in solving
the eternal question "Whatthehell did I buy and how do I use it?)

WDSmith






Date: Wed, 07 Nov 2001 16:20:55 -0000
From: stevesng@...
Subject: Re: DC motor field question

Murry,

A compound wound DC motor has multiple field windings which
can be configured to operate some of the field as a shunt
and some of the field as series. This allowed controls that
had variable speed and some degree of feedback regulation
without resorting to complicated electronics. The purpose
of the multiple windings was not <SNIP>