The overload protector is also called an excessive protector, a torque clutch, a safe clutch, a torque holder, a friction clutch, etc.It consists of dual -metal thermal components, action mechanisms, frequent open contacts, reset buttons, etc.When the motor is overloaded, the current becomes larger, and the overload protector will drive the switch to the card, thereby playing a certain protective role in the motor.
The role of overload protector
1. current load protection: The current load and the continuous overcurrent time reaches the setting value of the overcurrent time, the overload protector is automatically removed, and it can automatically reset after 5 minutes.After the deduction, the overload protector displays the current value of the maximum phase.The range adjustment range of over -current time is 0.2 to 30s, the repetitive error of overcurrent time is ± 5 [%], and the setting error of the overcurrent time ± 10 [%].2. Short -circuit protection: When the ratio of load current to the current fixed value of the current exceeds a certain value, it can be regarded as a short circuit. The overload protector is deducted within 0.5s.Electric: 2 to 4.5 times.Rat cage motor: 2 to 9 times.Other electromechanical equipment: refer to the above two options.After the overload protector is removed, the digital tube is displayed as "SHORT", and the instantaneous multiplex indicator lights are lit.3. Protection of lack of phase: The current in any phase of the three phases is less than one -third of the fixed value of the minimum current, and when the duration reaches a certain time, the overload protector is automatically deducted. This time is the lack of phase.Digital tubes are displayed as "PHASE" during the deduction.4. Phase imbalance protection: three -phase current imbalance reaches 50 [%] and the duration reaches a certain time value. The overload protector is automatically removed. This time value is the imbalance time.
Overload protector standard
Standard: The overload protector is a circuit protection device designed according to the actual needs of the electrical control industry. It uses single -chip microcomputer technology with complete functions, reliable movements, strong anti -interference ability, and adapting to a harsh working environment.It can provide effective protection for electrical systems, mouse cage motors, and winding motors, short circuit, short -term, phase imbalance, error phase and startup process (avoided the current).
Overload protector symbol
Use FR to represent a heat component in a box.The current overload and overloaded protector is usually called: torque holder, excessive protector, torque clutch, torque clutch, force limiter, axial load overload protector, torque limiter, safe clutch, safety couplet, limit force, limited forceClutch, clutch -limited force, roller clutch, friction clutch.The role of overload protector: It is often used between the main and passive side of the power transmission. When the overload failure occurs (the torque exceeds the set value), the torque limiter will be separated, which effectively protects the drive machinery and load;Common forms are: rubbing torque limiter and roller torque limiter.The installation structure of the torque limiter includes: shaft-shaft, shaft-flange, shaft-synchronous belt wheel, shaft-sprocket, shaft-gear, shaft-band wheel, etc.
Principles of overload protector
The overload protector is sampled by a current transformer, which converts the load current per phase to a voltage signal that is proportional to it.And compare with the corresponding conditions, and then output the results.

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