Bộ giới hạn quá tải cần cẩu
Các thông số chính:
- Độ chính xác ≤5%F.S.
- Cảnh báo 90%, báo động 105%
- 130% điều khiển tức thì, xuất ra một bộ tiếp điểm rơle
- Công suất 10A, 380V
- Điện áp nguồn AC 380 V hoặc 220 V/50 Hz
- Nhiệt độ môi trường -20～+60℃/90%RH
- Cảm biến có cấp độ bảo vệ IP65,
- Thiết bị có cấp bảo vệ IP42
Overview of QCX Crane Overload Limiter
Cái QCX Crane Overload Limiter is one of the most commonly used safety devices on double-girder cranes. It is designed to enhance operational safety by preventing overloading, thus protecting both equipment and personnel. The system typically consists of three main components: a sensor, a junction box (amplifier box), and a control instrument.
Các tính năng chính
- Versatile Sensor Compatibility:
- The QCX instrument can work with various types of sensors and support custom non-standard functions to meet diverse user requirements.
- High Accuracy:
- Measurement accuracy: ≤5% F.S.
- Warning and Alarm Mechanisms:
- 90% Load: Pre-warning alert.
- 105% Load: Alarm activates.
- 130% Load: Immediate control, outputs a relay contact to cut off the lifting motor circuit.
- Robust Electrical Specifications:
- Relay capacity: 10A, 380V
- Power supply: AC380V or 220V/50Hz
- Environmental Adaptability:
- Operating temperature: -20℃ to +60℃
- Humidity tolerance: 90% RH
- Protection Ratings:
- Sensor: IP65
- Instrument: IP42
- Optional Features:
- 4-20mA Interface: For seamless integration with external systems.
- Large Screen Display: To enhance visibility of operational data.
- Additional Control Outputs: For extended functionality.
Key Functions
- Load Monitoring: Displays the weight of lifted loads in real time.
- Alarm System:
- Visual and audible warnings for overloading conditions.
- Automatic cutoff of the lifting motor circuit at critical load thresholds.
- Tăng cường an toàn: Prevents equipment damage and accidents caused by overload.
Working Principle
- Weight Measurement:
- When the crane lifts a load, the sensor detects the weight.
- The sensor converts the weight into a small voltage signal.
- Signal Amplification and Processing:
- The signal is amplified in the junction box and transmitted to the control instrument.
- A high-resolution A/D converter converts the amplified signal into a digital format.
- Data Analysis:
- The microcontroller processes the digital signal, calculates the weight, and compares it with the rated capacity.
- Safety Actions:
- If the weight reaches 110% of the rated capacity, the system outputs a normally closed relay contact signal.
- This signal cuts off the lifting motor’s power supply to prevent further operation.
- Display and Alerts:
- The system displays the weight and triggers alarms (visual and audible) for pre-warning and overloading conditions.
Ứng dụng
Cái QCX Crane Overload Limiter is essential in industries where safety is critical, including:
- Metallurgy
- Machinery
- Khai thác
- Railways
- Ports
- Warehousing
Its ability to prevent overloading ensures modernized and safe operations in these sectors.
Kết luận
Cái QCX Crane Overload Limiter is an indispensable safety mechanism for double-girder cranes. By offering accurate load monitoring, reliable alarms, and automatic motor cutoffs, it minimizes risks associated with overloading and contributes significantly to modern industrial safety standards.
Sensors with shaft housings and bases, combined with QCX-M type instruments, are the most commonly used form of lifting weight limiters. The dimensions of standard products are shown in the following table. For example, the order model is: “QCX-M-4-20t/170-320”.
Sensors for large tonnage limiters are generally customized according to user drawings. The series dimensions in the following table are summarized based on the order drawings of major Chinese crane manufacturers for reference when new users order or design non-standard products.
HLF-3A series sensors consist of two parts: sensors and pads. They are mainly installed under the two ends of the fixed pulley shaft of the crane to withstand the pressure generated by the pulley block. Generally, two sensors are used in a group. They are often used in occasions with relatively high measurement accuracy requirements, such as crane electronic scales.
