Sensor actuator manager

A wide range of conttol systems is used in household appliances. A standard conttol loop consists of sensors, control units and actuators. The appliances become more powerful and efficient, as the technology is developed and integrated into microsystems. Matchbox-sized sensors can be equipped with wireless radio transceivers and their own miniature operating system to tiansmit continuous data to the facility manager. 

In the field, the topic of process control includes the selection and installation of sensors, transmitters, transducers, actuators, valve positioners, valves, variable-speed drives, switches and relays, as well as their air supply, wiring, power, grounding, calibration, signal conditioning, bus architecture, communications protocol, area classification, intrinsic safety, wired interlocks, maintenance, troubleshooting, and asset management. 

In this system, the sensor manager receives data from the sensors that are monitoring the eqnipment under control (EUC). This information is collected by the manager and sent to the monitor and the two controllers. Based on the information sent from the sensor manager, the monitor selects which controller to be nsed. The switch will receive input from the monitor as to which controller to take its input from. Notice that both controllers continuously receive data and sends output. It is only up to the monitor to decide which of the controllers that actually will be allowed to control the system. Data from the selected controller will be sent to the actuators which in turn control the EUC. 

Control zone This is the area of connectivity to control systems such as controllers (PLCs), human—machine interfaces (HMIs), and basic I/O devices such as actuators and sensors. Basically, there are three sections shown, namely, a management information system for plant management (which at times shares data with the database zone as discussed earlier), a main process control (namely, closed/open loop control system and data monitoring), and an applicable area control (e.g., choke kill control in offshore drilling, or offsite control like a coal handling plant in a power station). All I/Os are connected to this zone either by hardware directly or by a fieldbus system. This zone has very high priority and firewalls like a control firewall may be deployed. Additional external firewalls may also be used. 

In summary, we are therefore concerned with the operation and maintenance of sensors, controllers, actuators, valves, dampers, motors, the infrastructure connecting them to the mechanical equipment, and finally, when installed, all related network components that feed into the human operator of a computerized management and control system. 

As part of this process, we need to extend our view of the system we are seeking to assure. In the early days, the focus was on the technical system (hardware, software, sensor and actuators). In the future we need to think about the larger socio-technical system that includes the management, people and processes that interact with the technical system. 

The FLD-system provides an estimate of the fuel volume in the fuel tank to the driver along with a warning if the fuel volume drops below a predefined value. The functionality provided by the FLD-system is distributed across three Electronic Control Unit (ECU)-systems, i.e. an ECU with sensors and actuators, in the Electronic/Electrical (E/E)-system Engine Management System (EMS), Instrument Cluster (ICL), and Coordinator (COO). The ECU-systems also interact with the fuel tank that is outside of the E/E-system. COO estimates the fuel volume in the tank by relying on the output of a Kalman filter that, in turn, relies on a signal of a sensor measuring the fuel level in the tank and an estimate of the current fuel consumption provided by EMS, as inputs. The estimated fuel... 

A control system is centralized if it is managed by a unique computer that receives the inputs from all sensors and gives the command output to all actuators. The system is decentralized... 

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