Powering a 208-230 volt motor...question

[William R. Walsh]

Hello all...

I was recently given a small furnace blower unit with motor. I'd admit that
it was so small I made the assumption it ran on 110 volts AC and powered it
as such for a quick "go/no go" test since it had been sitting out in the
weather. It ran, but only very slowly and only for a few seconds until I
pulled the plug. Nothing got hot, no apparent damage was done.

After extricating the motor from a heavy load of restaurant grease, I found
that it is really a 208-230 volt single phase motor. (I'm in the US for what
it's worth.) It has four speeds and is wired something like this per the
label and contents of the wiring box:

BROWN - Capacitor
ORANGE - Capacitor
ORANGE - Line (hot)
SPEED1, 2, 3 or 4 would be connected to the other hot line depending upon
which one you want to choose.

I don't have easy access to a 220 volt power source. I could arrange things
so that I do, but that's a lot of work when I have this handy, sufficiently
heavy 110 to 220 step up transformer available! I'd like to know if it would
be safe to power the motor with that transformer for testing purposes. (My
plan, should the motor work, is to clean it up and sell or trade it for a
110 volt motor to use with the blower wheel.)

William

 

[hr(bob) hofmann@att.net]

On Feb 3, 6:46 pm, "William R. Walsh"
<newsgrou...@idontwantjunqueemail.walshcomptech.com> wrote:

Hello all...

I was recently given a small furnace blower unit with motor. I'd admit that
it was so small I made the assumption it ran on 110 volts AC and powered it
as such for a quick "go/no go" test since it had been sitting out in the
weather. It ran, but only very slowly and only for a few seconds until I
pulled the plug. Nothing got hot, no apparent damage was done.

After extricating the motor from a heavy load of restaurant grease, I found
that it is really a 208-230 volt single phase motor. (I'm in the US for what
it's worth.) It has four speeds and is wired something like this per the
label and contents of the wiring box:

BROWN - Capacitor
ORANGE - Capacitor
ORANGE - Line (hot)
SPEED1, 2, 3 or 4 would be connected to the other hot line depending upon
which one you want to choose.

I don't have easy access to a 220 volt power source. I could arrange things
so that I do, but that's a lot of work when I have this handy, sufficiently
heavy 110 to 220 step up transformer available! I'd like to know if it would
be safe to power the motor with that transformer for testing purposes. (My
plan, should the motor work, is to clean it up and sell or trade it for a
110 volt motor to use with the blower wheel.)

William

Just monitor the 220 V output of the step-up transformer to see that
it doesn't go much below 220V while you're testing the motor. A
momentary dip when first starting up shouldn't do any damage. As long
as it goes back to 220V, you probably aren't overloading the step-up
transformer. You can also get 220V using a 1-1 transformer by
connecting the primary of the transfomer to the 110V line and
connecting one output connection of of the transformer to the hot side
of the 110V line.The toutput in series with the 110V power line will
get you 220V. If you get the windings reversed, you will measure 0V
across the total output ples line. If so, reverse either the primary
or secondary of the transformer and you will have the 220V. Just be
sure the primary and secondary windings are totally isolated.