FBM206 Foxboro FOXBORO Controller, Shanghai Sijian Intelligent Technology Co., Ltd. is engaged in technical development, technical consultation, technical transfer in the fields of intelligent technology, information technology, and automation technology. Sales of electrical equipment, automation equipment, electronic products, communication products, and electromechanical products. Industrial automation products: PLC, DCS, sensors, frequency converters, encoders, relays, servo drives, soft starters, touch screens. Brands involved in the products include: Eurotherm, Schneider, Siemens, ABB, SICK, P+F, E+H, Yokogawa, Yamakawa, Mitsubishi, Emerson, Honeywell, FANUC, GE, Eaton Electrical, CT,
FBM206 Foxboro FOXBORO Controller, in people's impression, the computing speed of PLC is much faster than that of DCS. From a certain perspective, this is indeed true. PLC executes logic operations very efficiently, completing a 1K logic program in less than 1 millisecond, and its control cycle (taking DI input directly to DO output as an example) can be controlled within 50ms; while DCS uses the same method when processing logic operations and analog operations, and its control cycle is often above 100ms. When we compare using the PID algorithm, we can find that a PLC executes a PID operation in a few milliseconds, while the NETWORK6000+DCS T2550 controller also takes 1 millisecond to solve a PID, indicating that the actual computing capabilities of PLC and DCS are comparable, and some models of DCS controllers are even stronger. The difference in control cycles is mainly related to the controller's scheduling design. New DCS controllers have learned from the design of large PLCs and have significantly improved performance in terms of control cycles. Taking the NETWORK6000+DCS T2550 controller as an example, the controller can set four tasks with different priorities, and the operation cycle can be set to 10ms. Combined with high-speed I/O cards, the control cycle can reach 15~20ms. Analog operations are set in other tasks with longer cycles.
We know that a PLC controller can often handle thousands of I/O points, while a DCS controller can generally only handle hundreds of I/O points. From the requirements of a distributed system, centralized control is not allowed. Controllers with too many points are useless in practical applications. DCS developers simply do not have the need to develop controllers with many I/O points; their main focus is on providing system reliability and flexibility. PLCs are different. As a flexible control device, they have very strong point-handling capabilities.