IEC 60870-4:1990

FOREWORD
PREFACE
INTRODUCTION
1 Scope
2 Object
3 Classification of operational parameters
3.1 Reliability
3.2 Availability
3.3 Maintainability
3.4 Security
3.5 Data integrity
3.6 Time parameters
3.7 Overall accuracy
4 Expandability
5 Influence of telecontrol equipment on the environment
5.1 Electrical influence
5.2 Acoustic noise
5.3 Thermal influence
APPENDIX A - Measures to enhance system performance
APPENDIX B - Evaluation of expandability
TABLES:
1 Reliability classes
2 Availability classes
3 Maintainability classes
4 Repair time classes
5 Data integrity classes
6 Separating capability classes
7 Time resolution classes
8 Overall accuracy classes
9 Starting current classes
B.1 Extensions to process data
B.2 Extensions to application functions
B.3 Extensions to additional processing functions
B.4 Extensions to data transmission
FIGURES:
1 Processing of analog information
2 Noise criteria (NC) curves for speech communication

Deals with those characteristics which affect the performance of telecontrol systems and relates the characteristics to the application and processing functions. Establishes a set of rules to assess and specify the performance requirements of telecontrol systems; where feasible, performance classes have been specified for each of the properties covered.