"Allan" wrote in message
...
On Friday, 6 March 2015 07:37:11 UTC, Paul Conners wrote:
180 vdc, 1 hp, pm motor.

with dmm what should be the first tests? motor is in a difficult location
to
examine visually so i'd like to start with electrical evaluation.

it measures 1.2 ohms between the 2 armature leads.

thanks.

That's the problem trying to measure motors. If it's ok it's always going to
read low ohms, but maybe it should read 3.2ohms (eg) and has shorted turns
(eg), how would you ever know? If on the other hand it measured K ohms it
would be faulty. An insulation test from windings to armature would be more
appropriate. If that's ok give it a spin (I mean apply power).

+++++++++++++++++++++++++++++++++=

The resistance sounds too low. Can you rotate the armature and re measure at
a different point?

A 180 volt DC 1 hp motor should require around 5 amps or less at full load.
I would expect somewhere around 40-50 ohms when running under full load.

But as others have said, you want to check from the armature to frame
ground. Any resistance might be bad.


Regards