NDD3B(JD-5B) Motor protector

Product overview

NDD3B series integrated motor protector (hereinafter referred to as protector) is suitable for AC 50Hz, rated working voltage AC380V and below power supply circuit to form a motor control circuit with AC contactor and other switching appliances. When the main circuit of the motor is in an abnormal working state such as phase failure or overload, the contacts of the switching device should be disconnected in time, and the three-phase power supply of the motor can be disconnected to quickly and reliably protect the motor. The protector adopts a potentiometer quantitative setting method, which directly adjusts the setting current of the protector according to the rated current calibrated on the motor nameplate, which is more convenient and intuitive than the setting method that does not have quantification and needs to start the motor setting, but cannot accurately tune to the motor rated current. . The protector adopts intelligent multi-segment inverse time protection technology under the control of overcurrent rate, and the inverse time limit has excellent performance continuous adjustable technology, which can meet the needs of various motors from light load to heavy load starting.
This series of protectors meet the GB14048.4 standard.

Wiring Diagram

Outline and installation dimension drawing

Overload protection inverse time characteristic diagram

Application circuit example

KM: AC contactor QA: start button TA: stop button H1 ~ H3 protector threaded hole
Note: The protector and ac contactor control power supply must be in phase