Microprocessor-based thyristorized control system for speed control of coiler motor

A microcomputer system developed for the real-time speed control of a coiler-motor in a wire rod mill at the Bhilai Steel Plant, India, is discussed. The software permits the dynamic control of the coiler motor speed and also controls the tensionless back-end problem of the wire rod, resulting in considerable reduction in metal loss and production delay. The net annual saving due to introduction of the system is Rs. 6.2 million (around $0.50 million), and since the cost of implementation of the system is Rs. 5.3 million, the pay-back period is only ten months