I have searched several forums and found a lot of interesting stuff, but nothing yet that really applies to my situation. I have an old Westinghouse FH motor 1 1/2HP single phase brushed AC motor. There are four wires coming out of it. The wires are labeled T1, T2, T3, and T4. It is currently being used as a motor for a lathe. The T1 and T2 wires are joined together. And the T3 and T4 wires are joined together. I have the leads connected to a drum switch, but no matter what polarity is provided the Motor always spins one direction CCW. I don't see how reversing the polarity doesn't cause the direction to change. It doesn't appear to have a capacitor. I inherited the motor wired in this condition and have poked around on it a bit with swapping leads and other stuff but cant get it to run in any other configuration. Any knowledge is appreciated.

Wires Motor Plate

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    \$\begingroup\$ A photo of the motor and wiring would be useful. If there are brushes then let us see them. "I don't see how reversing the polarity doesn't cause the direction to change." The mains does that for you 50 or 60 times a second without you doing anything. \$\endgroup\$ – Transistor Mar 23 at 17:20
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    \$\begingroup\$ You first need to determine what kind of motor it is. Since you have said that it is brushed, why have you applied the [brushless-dc-motor] tag? It seems likely the motor is a universal motor. That would have a commutator. There are also motors with slip-rings, wound-rotor induction motors. There are also repulsion motors that have commutators. A universal motor can be reversed by reversing the rotor connection with respect to the stator. The motor may need to be taken apart for access to do that. \$\endgroup\$ – Charles Cowie Mar 23 at 17:43
  • \$\begingroup\$ Is there a nameplate on the motor? \$\endgroup\$ – Transistor Mar 23 at 18:29
  • \$\begingroup\$ Ill get some better photos tomorrow. For now this is the best one I have. I will have to do some research as well to determine what type it is. Thank you both. \$\endgroup\$ – Derek Latimer Mar 23 at 18:30
  • \$\begingroup\$ imgur.com/a/9QcytpS \$\endgroup\$ – Derek Latimer Mar 23 at 18:34

Old Westinghouse Type FR motors were what is called an Induction / Repulsion motor, a very early type that is now no longer made because Capacitor Start motors are simpler and easier (and reversible). Yours probably dates back to the 1920s or 30s, maybe the 40s pre-WWII, but not younger than that. The brushes are used in acceleration only by creating repulsion with the stator windings, but are moved out of the way via a centrifugal mechanism as the motor speeds up. The video below shows the basic concept, albeit in an earlier form where the brushes were moved manually. https://www.youtube.com/watch?v=_KdaipeodLo

The thing about those motors was, they are not reversible. Sorry.

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  • \$\begingroup\$ Note 10-8-36 is stamped on the nameplate just below and to the right of the top rivet. \$\endgroup\$ – Charles Cowie Mar 26 at 14:06
  • \$\begingroup\$ Thank you very much! \$\endgroup\$ – Derek Latimer Mar 26 at 15:51

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