1-4 F60 Feeder Protection System GE Multilin1.2 UR OVERVIEW 1 GETTING STARTED1 The direct inputs and outputs provide a means of sharing digital point states between a number of UR-series intelligentelectronic devices (IEDs) over dedicated fiber, RS422, or G.703 interface. No switching equipment is required as the IEDsare connected directly in a ring or redundant (dual) ring configuration. This feature is optimized for speed and intended forpilot-aided schemes, distributed logic applications, or the extension of the input/output capabilities of a single relay chassis.1.2.3 SOFTWARE ARCHITECTUREFirmware is the software embedded in the relay in functional modules that can be installed in any relay as required. This isachieved with object-oriented design and programming (OOD/OOP) techniques.Object-oriented techniques involve the use of objects and classes. An object is defined as “a logical entity that containsboth data and code that manipulates data.” A class is the generalized form of similar objects. By using this approach, onecan create a protection class with the protection elements as objects of the class, such as time overcurrent, instantaneousovercurrent, current differential, undervoltage, overvoltage, underfrequency, and distance. These objects represent com-pletely self-contained software modules. The same object-class concept can be used for metering, input/output control,software interface, communications, or any functional entity in the system.Employing OOD/OOP in the software architecture of the F60 achieves the same features as the hardware architecture:modularity, scalability, and flexibility. The application software for any UR-series device (for example, feeder protection,transformer protection, distance protection) is constructed by combining objects from the various functional classes. Thisresults in a common interface across the UR series.
