Overload limiter for single beam Overhead crane

Installation method and working principle of overload limiter for single beam Overhead crane
Lifting weight limiter, also known as overload limiter, is a safety protection device for lifting machinery, which is specially used for electric hoist single and double beam cranes of various models and specifications.
The device has the functions of audible alarm, immediate alarm, cutting off the crane lifting motor circuit and displaying the weight of lifting objects, which can avoid equipment and personal accidents caused by overload of lifting equipment.
The lifting weight limiter consists of two parts, sensor and controller. When the lifting machinery lifts a heavy object, the weight is transmitted to the sensor to cause a slight voltage change, which is amplified by the instrument amplifier and then converted into a digital signal by the high-resolution a/d converter. The digital signal is directly read by a single-chip computer and converted into a weight value after processing. Compared with the rated value, if the value reaches 110% of the rated value, a pair of passive relay contact signals (normally closed) are output to cut off the power supply of the lifting motor. In addition, the weight value can be sent to the controller for processing according to the command of the controller, and then the rated weight, lifting weight pre alarm and alarm sound are displayed.
The lifting mechanism of the electric single beam crane is an electric hoist, so the installation form of the lifting weight limiter on the electric single beam crane depends on the installation position of the load sensor on the electric hoist. Generally, there are three installation forms of crane limiter on electric single beam crane: fixed pulley type, hook type and wire rope type.