One of the things I salvaged from the farm was an old Delco electric
motor - Model A8280CC. This is an oooold motor - it's got oil caps to
oil the shaft bearings - sleeve bearings, I'm sure.

So I'm planning on aquiring a Beal Buffing System sometime in the not
too distant future and I was digging around in my box of old electric
motors and came on this one. 1/3 hp, 1750 rpm, just what the doctor
ordered. When I wiped of the plate, there was a note stamped on it -
to referse the direction of the motor, switch the red leads. Oh my!
Now I'm seeing a buffing/honing system!

I took the plate off the connection point and there were four posts
sitting there. Hmmm. The only current the the farm was straight 120,
never anything fancy like 3-phase or anything, so I'm puzzled - where
do two hot wires go, that can be reversed? Google the model number,
nothing.

So I hauled it down to a local electric motor repair shop and asked
them if they could tell me how to wire it up. The fellow poked around
for a minute, wiped some crud off the interior, and showed me the two
red wires in there that were to be switched. He said to just put the
common and power leads across the two top posts, didn't matter which
way.

I hooked up a power cord and slowly inserted the plug - sizzle crack!
The circuit breaker did it's job. Ok, maybe it does make a difference
which way it's wired - switched the wires, plugged it in, no sizzle
crack, but the circuit breaker opened.

I have another motor, 3/4 horse power farm duty motor I could use, but
I don't think it can be reversed. I'm going to take the Delco back and
see how much they'd charge to work on it. See if they have a
reversible motor for less money. I could tear the Delco down, but I
wouldn't know what to look for.

JW

I think you will find that one each red wire is currently connected to one
each black wire, and so reversing the red wires reverses the relative phase
of hte starting motor.

typically, there is a run winding and a start winding. the start winding is
switched through a centrifugal switch.

There are diagrams on line for many motors - have you tried looking? have
you used an ohmmeter to see what is what with those posts? It sounds like
you connected the power across the start switch, which would not be a good
thing

"John Weeks" wrote in message
...
One of the things I salvaged from the farm was an old Delco electric
motor - Model A8280CC. This is an oooold motor - it's got oil caps to
oil the shaft bearings - sleeve bearings, I'm sure.

So I'm planning on aquiring a Beal Buffing System sometime in the not
too distant future and I was digging around in my box of old electric
motors and came on this one. 1/3 hp, 1750 rpm, just what the doctor
ordered. When I wiped of the plate, there was a note stamped on it -
to referse the direction of the motor, switch the red leads. Oh my!
Now I'm seeing a buffing/honing system!

I took the plate off the connection point and there were four posts
sitting there. Hmmm. The only current the the farm was straight 120,
never anything fancy like 3-phase or anything, so I'm puzzled - where
do two hot wires go, that can be reversed? Google the model number,
nothing.

So I hauled it down to a local electric motor repair shop and asked
them if they could tell me how to wire it up. The fellow poked around
for a minute, wiped some crud off the interior, and showed me the two
red wires in there that were to be switched. He said to just put the
common and power leads across the two top posts, didn't matter which
way.

I hooked up a power cord and slowly inserted the plug - sizzle crack!
The circuit breaker did it's job. Ok, maybe it does make a difference
which way it's wired - switched the wires, plugged it in, no sizzle
crack, but the circuit breaker opened.

I have another motor, 3/4 horse power farm duty motor I could use, but
I don't think it can be reversed. I'm going to take the Delco back and
see how much they'd charge to work on it. See if they have a
reversible motor for less money. I could tear the Delco down, but I
wouldn't know what to look for.

JW


** Posted from http://www.teranews.com **

On Sat, 1 Nov 2008 17:18:22 -0600, Bill Noble wrote
(in message ):

I think you will find that one each red wire is currently connected to one
each black wire, and so reversing the red wires reverses the relative phase
of hte starting motor.

typically, there is a run winding and a start winding. the start winding is
switched through a centrifugal switch.

There are diagrams on line for many motors - have you tried looking? have
you used an ohmmeter to see what is what with those posts? It sounds like
you connected the power across the start switch, which would not be a good
thing

"John Weeks" wrote in message
...
One of the things I salvaged from the farm was an old Delco electric
motor - Model A8280CC. This is an oooold motor - it's got oil caps to
oil the shaft bearings - sleeve bearings, I'm sure.

So I'm planning on aquiring a Beal Buffing System sometime in the not
too distant future and I was digging around in my box of old electric
motors and came on this one. 1/3 hp, 1750 rpm, just what the doctor
ordered. When I wiped of the plate, there was a note stamped on it -
to referse the direction of the motor, switch the red leads. Oh my!
Now I'm seeing a buffing/honing system!

I took the plate off the connection point and there were four posts
sitting there. Hmmm. The only current the the farm was straight 120,
never anything fancy like 3-phase or anything, so I'm puzzled - where
do two hot wires go, that can be reversed? Google the model number,
nothing.

So I hauled it down to a local electric motor repair shop and asked
them if they could tell me how to wire it up. The fellow poked around
for a minute, wiped some crud off the interior, and showed me the two
red wires in there that were to be switched. He said to just put the
common and power leads across the two top posts, didn't matter which
way.

I hooked up a power cord and slowly inserted the plug - sizzle crack!
The circuit breaker did it's job. Ok, maybe it does make a difference
which way it's wired - switched the wires, plugged it in, no sizzle
crack, but the circuit breaker opened.

I have another motor, 3/4 horse power farm duty motor I could use, but
I don't think it can be reversed. I'm going to take the Delco back and
see how much they'd charge to work on it. See if they have a
reversible motor for less money. I could tear the Delco down, but I
wouldn't know what to look for.

JW


** Posted from http://www.teranews.com **

expanding on what Bill Noble said, the speed of your motor tells us that it
is a 4-pole motor. It is a split-phase motor, also called a squirrel-cage
motor. It has 2 sets of windings. The run windings are large, compared to the
"start" windings, and are always energized. The "start" windings are
connected in parallel with the run windings and have relatively few turns in
them. They are physically displaced around the motor field frame, from the
run windings, and when they are energized, they create an effect similar to a
rotating magnetic field in a 3 phase motor. When the motor gets up to around
70% of full running speed, a centrifugal switch kicks out and disconnects the
start windings from the power, so only the run windings are left energized.
A motor of this type is easily reversed by simply swapping the start winding
leads. This reverses the apparent rotation of the magnetic field and thus the
rotation of the motor.
If the centrifugal switch is open, then only the main winding is connected,
and the motor will simply hum until the circuit breaker or fuse opens. Other
electrical flaws can produce the same result.

Depending on your circumstances, the motor condition, and how friendly your
repair shop is, it might be cheaper to get a new motor than fix the old one,
in this day and age.
YMMV
tom koehler

--
I will find a way or make one.