i have a tuscan engineering 240 v motor it has a capacitor inside the motor and the rest of the iwres are joined inside the motor. i have tried sewaping the newtral ane live around in the plug but the motor still goes the same way. i have tried stripping the motor down to put the motor shaft in from the other direction but it does not seem possible to do. probably simple to swap a couple of wires but i do not know whitch.

DanielF

Jim,

The motor should have two stator windings, one end of each being connected together (the 'cold' end), which in turn connects to the mains neutral. For the 'hot' ends, one will go direct to the mains active, and the other through the 'start' capacitor to the mains active.

To reverse the direction you need to swap those two 'hot' connections, so the one previously direct to active now goes via the capacitor, and the one previously via the capacitor now goes direct to active.

But before you do that, I'd recommend measuring the resistance of each winding with your multimeter, to check that they are the same resistance (hopefully indicating a 'symmetrical' motor winding arrangement).

If they're not the same resistance, you shouldn't swap the windings, as you may cause overheating, a short circuit and a fire!

Daniel

jimstockingfiel

i tried doing that i have reversed the motor but it struggles to start under load needs to be started by hand what have i done wrong?

Stratmando

Daniel, if this was wired for 120 volts, would the 2 windings be in parallel, instead of series?
Then if you swaped 1 of the windings end to end, it would reverse. And is their a site or somewhere that show how to determine what is what, like the 6 wire motors, with the numbers 1 + 3, 2 + 4, and the 5 and 8 for reversing, and the wires are NOT identified, Thanks.

DanielF

Sorry for the slow reply – busy preparing for a 4-week o'seas holiday!

Stratmando, I think you're possibly thinking of a 'universal' motor, with both stator (field) and rotor windings (with a commutator). That type of motor can be connected in series or parallel depending on the application and supply voltage. But Jim's motor is an induction motor, so it has no rotor winding, just a 'squirrel cage'. Have a look at Single-phase induction motors : AC MOTORS for an explanation of how it works, though that site requires some engineering knowledge to fully understand. The explanation for a 3-phase induction motor (and the squirrel cage) is a few pages back from there. In all cases, an induction motor requires a rotating magnetic field (to start, at least), and for a motor operating on a single phase, a capacitor is used to generate a pseudo 2nd phase to generate the rotating field.

Jim, did you measure the two winding resistances, and are they equal? Secondly, are you running it on the rated 240V supply? In north America this would require a 2- or 3-phase supply to your house/workshop, so you could connect from one phase to another (which I think only gives you ~210V anyway), or a step-up transformer. In civilised countries you would just connect from phase to neutral for 220 or 240V. Keep in mind that the torque available from the motor will vary as the square of the supply voltage, so if you tried to operate that motor on 120V, you'd only get 25% of its rated torque.

Note from the page linked above that some 2-phase motors have an extra capacitor switched-in during starting. Is there any chance yours is like that, and somehow the 'start' capacitor hasn't been correctly re-connected, or is faulty?

Daniel