Rob said:
Hi
hope some one can help me with this problem i have ....i just won on
ebay a 24 v dc Nelco motor with wound field and armature type
separately excited ?..when i tried to connect it to my 24 v battery
there are 4 connections? where do i put my positive and negative
terminals?..
thanks
Robert l
Hi, Rob. You haven't given us a lot to work with here. So I guess
you'll have to do some detective work yourself...
Based on the assumption that you've got a motor with 24VDC armature and
24VDC field, you should get your ohmmeter out (with the motor not
connected, of course). By checking for continuity between all the
wires, you should find two pairs where there's a fairly low resistance
between.
(The following advice only applies if that is true.)
Of those two pairs, it's a safe bet the one with the higher resistance
is the field. The lower resistance pair should be the armature. Also,
if there's no gearing, you should be able to manually turn the motor
shaft. You will find that the armature resistance will "blip" as the
brushes commute, whereas the field resistance will basically stay the
same.
Many times, the armature on DC motors made on this side of the pond
will be red (+) and black (-). Euro/Brit motors are more likely to
have brown (+) and blue (-) as the armature, but don't bet the farm or
the motor on it.
Remember, the field usually gets the fixed voltage, and the armature
gets the variable voltage to control motor speed.
Trust, but verify. Start things up with a current-limited power supply
and try "bumping" it, providing voltage to armature and field for half
a second. That should give you a clue if things are wired correctly.
And by the way, sorry for the sketchy answer. More information usually
results in a better response on s.e.b.
Good luck
Chris