A three-phase induction motor with a built-in fail-safe electromagnetic brake. The brake is spring-applied and normally engaged: a spring presses the brake disc onto the shaft, and energising the brake coil pulls it back electromagnetically to release the shaft. This logic makes the brake fail-safe — on loss of supply or a break, the shaft is held automatically. The coil is usually wired in parallel with the motor so the brake releases on start and applies on shutdown. Such motors are used in hoists, lifts, conveyors and machine tools where the shaft must be held firmly when stopped. The model shows the torque M, the brake-coil current and the brake state (applied/released).
This page is a utility for simulating induction motor with electromagnetic brake (3-phase) online with specified initial values.
Using the model. The three stator switches start the motor; the brake coil is fed from a separate source. As long as enough current flows in the coil the brake is released (brake released) and the motor runs up. Raise the coil-circuit rheostat with the slider: the coil current drops, and once it falls below the release current the brake engages (brake applied) — the shaft is held even with the stator energised. This makes the fail-safe braking principle clearly visible. The "load torque" slider sets the load. Scopes: stator current I(stator), brake-coil current I(coil) and voltage U(L1‑L2).
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