Safeguarding Crane Operations: Understanding Crane Overload Limiters

In lifting operations, the crane overload limiter is a crucial device used to control the maximum lifting load of a crane, ensuring the safety of the lifted load. This article delves into the types, working principles, and key detection functions of overload limiters, providing readers with a comprehensive understanding of their significance.

Types of Overload Limiters
Overload limiters are categorized into three types: mechanical, hydraulic, and electronic. With cranes adapting to market demands and advancements, mechanical and hydraulic types have been phased out, and the current trend favors electronic overload limiters. Electronic overload limiters consist of load sensors, electronic amplifiers, digital display devices, and limit switches. The load sensor can be installed above the hook or on the balance wheel, with strain gauges adhered to its surface, forming a strain gauge bridge. When the sensor experiences force, the bridge becomes unbalanced, generating a signal that is amplified for display, controlling limit switches to facilitate weighing and lifting load restrictions.

Working Principle
Overload limiters function by detecting parameters such as lifting weight, current, and voltage to protect the crane. Utilizing advanced technology, they issue timely warning and alarm signals to prevent overload operation and ensure operational safety.

Common Power Supply Voltage and Control Circuit Settings
The standard power supply voltage for overload limiters is AC220V 50Hz, 380V 50Hz, with control circuit settings at 24V~48V, AC220V/380V. Stable power supply and control circuitry are crucial for their proper functioning.

Weighing Error, Operating Temperature Range, and Applicable Crane Types
The weighing error of overload limiters is ≤5% F·S, with an operating temperature range of -30 to 80°C. They are suitable for various types of double girder bridge cranes, gantry cranes, and grab cranes ranging from 3t to 80t, catering to a wide range of lifting operations.

In conclusion, the crane overload limiter plays a vital role in ensuring the safety and efficiency of lifting operations. For reliable and safe lifting solutions, we recommend exploring our company's range of bridge crane products equipped with advanced overload limiter systems.