Winding And Unwinding Arrangement For Tension Control In Crane.

CUSTOMER NAME : India’s most technologically advanced Container Terminal’s
INDUSTRY : Port Industry
APPLICATION : High Speed (130mpm) Monospiral CRD for eRTG
LOCATION :  Nellore, Andhra Pradesh


The customer is one of the most technologically advanced Container Terminals in India powered by state-of-the-art handling facilities. The facility had an RTG which was converted to ERTG for energy saving. The eRTG needs power supply from a stationary source and cable management of the supply cable is vital, else would result in breakage of cable or even fatal accidents or damage to the drum of the eRTG. The modification required a highly reliable Cable Reeling Drum to be incorporated.


FEI after understanding and analyzing the system, suggested a winding and an unwinding arrangement as cranes move from one bay to another, but the power supply is taken from a stationary source through a power cable. Hence it very important to provide torque as per cable tension. In case of under tension, the cable can slack and in case of over tension, the cable can cut-off. The VFD used for winding & unwinding along with the PLC ensured that a precise Torque control is effected eliminating over-tension or slack in the cable as it risks cable damage. Fuji Electric’s PLC combining with the Drive and position limit switches enabled a precise Torque Control operation. 


Accurate required torque and cable tension are maintained for winding and unwinding. The customer benefitted by gaining a sturdy, highly reliable Drive system with a very intuitive and informative Graphic Console.