This instrument verifies the relationship between the armature steering and the direction of current and the direction of magnetic lines of force. Grasp the principle of rotation of the motor. This machine is mainly composed of base, rotating shaft, bracket, commutator, armature coil, pulley, pole shoe, permanent magnet, electric brush, terminal and other parts. This model features precision-engineered core components meeting strict teaching standards: permanent magnets measuring 22×20×20mm with magnetic flux density Br no less than 72mT, red N-pole and blue/white S-pole with precision-ground end faces for uniform magnetic field distribution; pole shoe arc radius of 23mm precisely matching the 42mm-diameter armature core arc for a uniform air-gap magnetic field; and symmetrically wound rotor coils with securely fitted core and shaft for sensitive no-lo Pay special attention to the two brushes before turning on the power to avoid contacting the same commutator segment to avoid short circuit. Permanent magnet N is extremely red, S is extremely white or blue, pay attention to the color code when installing.