PLC control of a cold store and ripening plant-a case history

The success of modern refrigeration methods, involving close control of cold store environments, is due in large part to the availability of low cost control systems employing intelligent programmable logic controllers, and PC-based SCADA (supervisory control and data acquisition) systems. TA Consultancy Services were tasked to supply the software-based control system for a multi-chamber cold store. Specific requirements of the control system called for were: monitoring of the complete cold store via a SCADA system; monitoring and control, via PLCs of evaporators, compressors, condensers, liquid pumps and ammonia detection; and a remote monitoring system