A VFD must provide precise control with high starting torque; smooth motor operation throughout starting and stopping phases; motor holding brake control; avoidance of load droop and sag; regeneration and braking capability during load lowering.

Speed Control

VFDs allow for precise control over the speed of the crane or hoist. This can be particularly useful in applications where delicate or precise movements are required, such as placing a heavy load in a specific location or moving hazardous materials. VFDs can smoothly ramp up or ramp down the motor speed, preventing abrupt starts or stops that can lead to load swing or even damage the equipment.

Load Control

In addition to speed control, VFDs also help with load control. By providing consistent torque, VFDs can prevent load slip or drop, ensuring safer operations.

Increased Lifespan

Since VFDs can minimize the wear and tear on motors by providing smooth starts and stops and reducing the chances of overloading, they can prolong the lifespan of the equipment.

Braking Control

In traditional crane and hoist systems, braking is often done mechanically, which can lead to wear and tear over time. However, VFDs can provide dynamic or regenerative braking, where the motor itself is used to slow down or stop the load. This can reduce the wear on mechanical brakes, prolonging their lifespan.

Synchronisation

In systems where multiple cranes or hoists need to work together to move a large or awkwardly shaped load, VFDs can help synchronize the movement of each motor to ensure smooth and coordinated operation.

Improved Safety

By providing better control over the speed, torque, and braking of the motor, VFDs can reduce the risk of accidents such as load drops or uncontrolled movements, thereby improving safety.

Maintenance Monitoring

Some advanced VFDs come with predictive maintenance features that monitor the condition of the motor and other equipment. By alerting operators to potential issues before they become serious problems, these VFDs can reduce downtime and repair costs.

By enhancing control, improving energy efficiency, and increasing safety, VFDs have become an integral part of modern crane and hoist operations. They allow for more precise and efficient operations, leading to cost savings and improved productivity.

Sumitomo Drive Technologies - products for Cranes & Hoists

Lafert Motor

High efficiency and customised electric motors for Cranes & Hoists applications

lafert.com

Power transmission products, gearboxes and gear motors for Cranes & Hoists applications

sumitomodrive.com

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