Common faults and solutions for electric chain hoists

As a key piece of equipment in modern industrial lifting operations, electric chain hoists are highly valued for their efficiency and safety. However, with frequent and long-term use, malfunctions and abnormalities are inevitable. To help users better understand the equipment's operating status and perform efficient maintenance, this article systematically summarizes common chain hoist failure symptoms, causes, and solutions, providing a practical guide covering both self-inspection and repair.

I. The Core Concept of Failure Prevention: Prevention is Better Than Repair

The best maintenance for any piece of equipment is proactive prevention. Although chain hoists are compact and feature delicate components, proper use and regular maintenance significantly reduce the probability of failure. Preventive maintenance includes:

Daily routine inspections before lifting;

Monthly thorough inspections of the chain, hook, brake, and electronic control system;

Maintenance intervals and spare parts replacement schedules based on operating frequency.

II. Common Fault Classification and Phenomenon Identification

1. Electrical Faults

Phenomenon 1: No response when pressing controller buttons

Cause: Power not connected, control circuit open, controller damaged

Handling: Check power indicator → Check wiring terminals → Replace controller

Phenomenon 2: Smooth lifting or lowering/stuck

Cause: Inverter fault, incomplete brake release, contactor damage

Handling: Restart the inverter → Test brake clearance → Replace contactor

2. Mechanical Faults

Phenomenon 1: Chain jamming, skipping, or kinking

Cause: Severe chain wear, insufficient lubrication, abnormal sprocket wear

Handling: Replace chain → Add special grease → Check and replace sprockets

Phenomenon 2: Hook deformation or sluggish rotation

Cause: Overload or hook material fatigue

Handling: Immediately replace the hook assembly and check whether overload protection is effective

3. Brake System Abnormalities

Phenomenon 1: Hook descends slowly after discharge

Cause: Electromagnetic brake wear, loose spring

Action: Replace brake pads → Adjust brake clearance → Reinstall springs

Phenomenon 2: Sudden drop during lifting (dangerous)

Cause: Brake failure or dislodged brake pads

Action: Emergency stop equipment → Inspect brake system → Replace entire brake assembly

4. Limit switch failure

Phenomenon: Hook continues to operate despite exceeding the limit

Cause: Damaged limit switch or incorrect wiring

Action: Test limit trigger points → Replace limit switches → Recalibrate limit distances

III. Recommended Self-Inspection Procedure (Daily + Periodic)

1. Daily pre-startup inspection items:

Power supply stability, emergency stop button reset;

Controller sensitivity, all buttons' responsiveness;

Chain rust, jamming, or kinking;

Hook safety buckle securely closed;

Any unusual noise, odor, or shaking. 2. Weekly/Monthly Inspection Recommendations:

Check the clearance between the motor and brake for a normal value (0.3-0.5mm);

Clean the electrical control box and tighten the terminals;

Lubricate the chain and check the tension;

Check the limit switch travel and position for correctness;

Test the sensitivity of the overload protector.

IV. Special Precautions and Safety Warnings

1. Overloading is strictly prohibited: Even if the equipment is equipped with standard overload protection, its limits should not be deliberately tested.

2. Operation with a fault is prohibited: If any unusual noise, odor, or control abnormality is detected, the equipment should be shut down and investigated immediately.

3. Maintenance must be performed with the power off: Maintenance with power on must be avoided to ensure operator safety.

4. Replacement of key components, such as motors, brakes, and electrical control boxes, must be performed by professionals with an electrician's license or with assistance from the manufacturer's after-sales service.

Conclusion: Trouble-free equipment comes from understanding the equipment.

The failure rate of a chain hoist is not predetermined; it is closely related to user awareness and operation. Establishing good usage habits and mastering quick troubleshooting techniques for common problems are key to extending equipment lifespan and ensuring operational safety.

We recommend that all users establish a standardized inspection schedule and provide systematic operator training after purchasing the equipment. If you encounter unresolved issues during use, please contact our technical support team. We will provide remote diagnosis and prompt service to ensure stable, safe, and efficient lifting operations.