Drives and Controls Magazine
Home
Menu
Crane software boosts safety and performance
Published:  20 October, 2008

ABB has developed optional crane control software for its drives rated from 0.55kW to 5.6MW. The dedicated software incorporates all of the functions commonly required for hoist, trolley and long-travel motions in industrial, harbour and tower cranes.

The software uses the company’s DTC (direct torque control) technology to enhance safety and provide accurate low-speed control with high levels of torque, with or without encoder feedback from the motor shaft. A library of 15 easy-to-program function blocks eliminates the need for an external PLC. The software can accommodate different start torque methods, and includes a brake monitoring function for start, stop or running sequences.

Integrated brake control logic uses torque memory and pre-magnetising to open and close mechanical brakes reliably. In master/follower applications, the drives for up to five motors can be interlinked by fibre optics. Other facilities include: a function for checking electrical and mechanical systems; a load speed control that maximises the hoist speed for a given load and ensures that there is sufficient torque in the field-weakening area; a “slow down” function that limits the speed to a safe level in critical zones; and a speed monitor function to ensure that the crane motor speed stays within safe limits.