Purpose of a soft starter UPTF EK-AV6
soft starters of the EK-AV6-xx-RS-Vx series manufactured by Energocomplekt JSC with a digital control system are designed for contactless soft start of asynchronous motors with a wound rotor. The devices can be used to start belt conveyors, lifting mechanisms, mills, crushers and other mechanisms with severe start-up conditions.
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soft starter for AD-FR type EK-AV6-1.0-RS-V1.3 UHL4 with one resistor unit.
EK-AV6-xx-RS-Vx is fully digitally controlled, can be used in automated manufacturing, controlled and monitored by a higher-level control system.
The EK-AV6-xx-RS-Vx soft starter provides:
- smooth start of the mechanism;
- work at a reduced (repair) speed;
- sampling of backlashes, gaps, "pretension";
- single-engine and multi-engine modes (coordinated operation of several soft starters for AD-FR);
- smooth regulation of engine start time;
- local (from the device door) or remote (according to the Modbus, Profibus DP protocol) control.
Composition
The product includes a cabinet of a thyristor converter with a control system, as well as one or more (depending on engine power) cabinets with starting resistances. The device is also equipped with a shunt contactor.
PRINCIPLE OF ACTION
The structure of the EK-AV6-xx-RS-Vx.
The electric motor starts as follows:
After connecting the stator of the electric motor to the network, voltage appears in the rotor of the electric motor. The control system changes the angles of thyristors control while a smooth increase in the rotor current occurs. After reaching the moment of rotation of the engine static load moment, the engine moves and begins to gain momentum.
To further increase the speed, the control system reduces the control angle of the thyristors of the rectifier. When the thyristors of the rectifier are fully open, the rotor current is limited by the resistance of the rheostats.
To further increase the speed, one of the rheostats is shortened, while the voltage of the rectifier is adjusted so that the rotor current before bypassing the resistor and after bypassing coincides. After that, the angle of control of the thyristors of the rectifier is reduced again to the full opening of the thyristors, after which the next rheostat is shortened in a similar way.
Thus, the launch takes place on four stages. After the full opening of thyristors at the last stage, the rotor is completely shortened by the contactor. The motor starting is complete.