Electric Motor in a Dishwasher

There is residual magnetism in induction motors.

GA for a correct answer (that few will either believe or understand!).

All my appliances; washer/dryer and dishwasher, have brushless DC motors...many newer appliance manufacturers use them.

It could be a synchronous type, either mains frequency or inverter driven. The mains driven drainage pump I replaced, from a washing maching machine (Maytag/Asco) looked 'shaded pole' but cogged 180 degrees strongly. That was an internal, permanent magnet rotor, synchronous type. It started in random direction, and its impeller was four radial blades. Do any of those recolections match your observations? External rotor type could exist too, attracting shards.

if as you say it does not have brushes and it has permanent magnets.

it would from your description not need any wires thus it would be impossible.

you need to check again can you see inside motor casing?

it is probable it is a squirrel cage rotor with wired stator coils ac fed, but there must be wires into motor.

please give motor a thorough check and report back

peterg7lyq,

My description "shaded pole like" was to describe the motor's stator construction.

Shaded pole motors (probably the most common 10W class mechanical AC motor construction) have a stack of laminations forming a rectangle with a central, rectangular, hole through each lamination. One leg has a circular cutout large enough to sever the leg, the squirrel caged rotor runs in this bore.On the opposite leg is the power AC winding. The AC field would not self start rotation but shading poles are copper rings around a fraction of the pole face. Current induced in the rings produceas a phase shifted magnetic field (wirh respect to the main field). The sum of the main and shifted fields produces a rotating field, dragging round the rotor.

That winding has leads! There are /were larger cylindrical shaded pole motors but I cannot recall any from the last 40 years

The permanent magnet in the rotor produces torque and inertia provides enough energy to continue rotation at synchronous speed.

Stepper motors are brushless...

It is an ECM (electronically commutated motor). They are heavily used in higher end appliances and furnaces due to their efficiency, low noise level and flexibility of application.

The motor is quite small, much smaller than in older dishwashers of the past. It is in a 2009 Tappan machine. it is now installed, so I don't have access to the motor any longer. The reason I ask this is I'm looking for an inexpensive DC motor to power the large scale locomotive I'm building. The motor looks just the right size for my purpose. It probably wouldn't work anyway as I am using 12V storage batteries, so the motor has to operate on 12V.

Gerard morin! Look him up. You just stumbled on to Tesla's secret!