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Reverse control of a three-phase electric motor. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Electric motors
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It is applied in the industry, in the load-lifting equipment, in the processing machines, in construction.
Rice. 1. Control scheme
The simplest and most common scheme for connecting control buttons, contacts and coils of magnetic starters.
Consider the direction of the electric current, in the operation of the circuit and its elements, the function Closed.
When you press a button Closed; via button Stop; contact K2.2, magnetic starter K2; contact KS1, limit switch; the circuit is closed.
Coil K1 retracts the anchor, closes the contact K1.1, the coil becomes self-feeding, the button Closed, you can let go; opens the contact K1.2, to block erroneous switching on of the coil K2; electric motor AD working.
When reaching the limit switch mechanism, its contact opens KS1, the circuit breaks; coil K1 turns off; electric motor AD has stopped.
Function operation Open, according to principle Closed.
Button Stop, can be used at any time during the operation of the electric motor AD; to open the power supply circuit of the coils K1 и K2 and self-feeding contacts K1.1 и K2.1.
Rice. 2. Power scheme
Motor power supply diagram AD, consists of two magnetic starters with power contacts K1 и K2.
When turning on the coil K1 or K2, power contacts are switched on K1 or K2, which are connected so that when switching they change the phasing of the motor connection AD, changing phases L1 и L2.
Publication: electro.narod.ru
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