1-4
L30 Line Current Differential System
GE Multilin
1.2 UR OVERVIEW
1 GETTING STARTED
1
c) UR SCAN OPERATION
The UR-series devices operate in a cyclic scan fashion. The device reads the inputs into an input status table, solves the
logic program (FlexLogic equation), and then sets each output to the appropriate state in an output status table. Any result-
ing task execution is priority interrupt-driven.
Figure 1–3: UR-SERIES SCAN OPERATION
1.2.3 SOFTWARE ARCHITECTURE
The firmware (software embedded in the relay) is designed in functional modules that can be installed in any relay as
required. This is achieved 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 contains
both data and code that manipulates that data”. A class is the generalized form of similar objects. By using this concept,
one can create a protection class with the protection elements as objects of the class, such as time overcurrent, instanta-
neous overcurrent, current differential, undervoltage, overvoltage, underfrequency, and distance. These objects represent
completely 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 L30 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. This
results in a common interface across the UR series.
1.2.4 IMPORTANT CONCEPTS
As described above, the architecture of the UR-series relays differ from previous devices. To achieve a general understand-
ing of this device, some sections of Chapter 5 are quite helpful. The most important functions of the relay are contained in
“elements”. A description of the UR-series elements can be found in the
Introduction to elements
section in chapter 5.
Examples of simple elements, and some of the organization of this manual, can be found in the
Control elements
section of
chapter 5. A description of how digital signals are used and routed within the relay is contained in the
Introduction to Flex-
Logic
section in chapter 5.
Summary of Contents for L30
Page 10: ...x L30 Line Current Differential System GE Multilin TABLE OF CONTENTS ...
Page 30: ...1 20 L30 Line Current Differential System GE Multilin 1 5 USING THE RELAY 1 GETTING STARTED 1 ...
Page 370: ...5 244 L30 Line Current Differential System GE Multilin 5 10 TESTING 5 SETTINGS 5 ...
Page 464: ...A 10 L30 Line Current Differential System GE Multilin A 1 PARAMETER LISTS APPENDIX A A ...
Page 600: ...C 30 L30 Line Current Differential System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Page 610: ...D 10 L30 Line Current Differential System GE Multilin D 1 IEC 60870 5 104 APPENDIX D D ...
Page 622: ...E 12 L30 Line Current Differential System GE Multilin E 2 DNP POINT LISTS APPENDIX E E ...
Page 634: ...F 12 L30 Line Current Differential System GE Multilin F 3 WARRANTY APPENDIX F F ...
Page 644: ...x L30 Line Current Differential System GE Multilin INDEX ...
