Electric motor direction indicating device
AssigneeWestinghouse Electric Corp.
InventorJan Vosicky
Life of this patent
Estimating the term…
Abstract
A direction indicating device for indicating the direction of rotation of a polyphase A.C. electric motor. A polyphase energy source having a frequency higher than the operating frequency of the electric motor impresses a rotating electromagnetic field in the windings of the motor. A pair of coil detectors, spaced a predetermined electrical distance apart, detects the rotating electromagnetic field and determines the direction of rotation of the electromagnetic field. The direction of rotation of the electromagnetic field, which is the same as the rotation of the electric motor, is displayed on a display apparatus.
Claims9
A direction indicating device for indicating the direction of rotation of an A.C. electric motor having windings thereon, said device comprising;
- a source of electrical energy producing an electromagnetic field within said windings,
- means for sensing said electromagnetic field in said windings, and
- display means for indicating the direction of movement of said electromagnetic field in said windings, the direction of movement of said electromagnetic field in said winding indicating the direction of rotation of said motor.
A gas turbine power plant comprising:
- a starting package having an A.C. electric motor disposed therein, said electric motor having windings thereon, and,
- an indicating device for indicating the direction of rotating of said electric motor, said indicating device comprising;
- an electrical energy source producing an electromagnetic field in said winding,
- means for sensing said electromagnetic field in said windings at a first and a second point, said electromagnetic field inducing a first and a second electric current in said sensing means, and,
- means for comparing the phase relationship between said first and said second electric currents to indicate thereby the direction of rotation of said electric motor.
A method of determining the direction of rotation of an electric motor comprising the steps:
- a. energizing the windings of said electric motor to produce a rotating electric field therein, and
- b. sensing the direction of rotation of said rotating electric field, said direction of rotation of said electric field corresponding to said direction of rotation of said electric motor.
Dependencies are inferred from the claim text.