HB 102-1997 (CJC 6)

1 - SAA HB102-1997 COORDINATION OF POWER AND TELECOMMUNICATIONS - LOW FREQUENCY INDUCTION (LFI) APPLICATION GUIDE TO THE LFI CODE
4 - PREFACE
5 - CONTENTS
9 - SECTION 1 INTRODUCTION
10 - SECTION 2 MECHANISM OF LOW FREQUENCY INDUCTION AND CALCULATION OF INDUCED VOLTAGES
13 - SECTION 3 PROCEDURES FOR MAKING CALCULATIONS AND DETERMINING BEST ENGINEERING SOLUTION
13 - 3.1 Calculation Procedure
15 - 3.2 Selection of Appropriate Induced Voltage Limit
15 - 3.3 Some Factors Considered by the Electricity Utility in Selection of Power Line Categories
18 - SECTION 4 EVALUATION OF FACTORS FOR CALCULATING INDUCED LONGITUDINAL VOLTAGES
18 - 4.1 Earth Fault Currents
18 - 4.1.1 Factors Affecting Fault Currents
19 - 4.1.2 Calculations of Fault Currents
22 - 4.2 Mutual and Self Impedances
22 - 4.2.1 Formulas and Nomogram for Calculations
23 - 4.2.2 Selection of Earth Resistivity Values
24 - 4.3 Shielding Factors
24 - 4.3.1 Fundamental Principles
26 - 4.3.2 Shielding Factors Relating to Power Lines and Power Cables
27 - 4.3.3 Shielding Factors Relating to Telephone Lines
28 - 4.3.4 Shielding by Adjacent Conductors
28 - 4.3.5 Shielding by Cable Sheaths
28 - 4.3.6 Shielding by Magnetic Loading
29 - 4.3.7 Shielding by Multiple Telecommunication Cables
29 - 4.3.8 Shielding by Environmental Metallic Conductors
30 - 4.3.9 Shielding by Earthing Spare Cable Pairs
30 - 4.3.10 Latent Shielding
31 - 4.4 Overvoltage Protection by Gas-Filled Protectors
33 - 4.5 Length of Exposure and Separation
33 - 4.5.1 General
33 - 4.5.2 Zone of Exposure for which Calculations may not be Required
34 - 4.5.3 Examples Where Calculations are Required
34 - 4.5.4 Summation of Exposure Sections
35 - 4.5.5 General Case
39 - SECTION 5 EXAMPLE OF CALCULATION
39 - 5.1 Typical Case
39 - 5.2 Details
39 - 5.3 Preparation and Assumptions
40 - 5.4 A Method of Making Detailed Calculations
40 - 5.4.1 Calculation of Currents for a Fault in the Power Line
45 - 5.4.2 Length of Exposure
45 - 5.4.3 Separation
45 - 5.4.4 Earth Characteristics
45 - 5.4.5 Average Mutual Impedance
45 - 5.4.6 Calculation of Induced Voltage
45 - 5.4.7 Calculation of Shielding Factor
47 - 5.4.8 Resultant Induced Voltage
47 - 5.4.9 Summary
48 - 5.4.10 Calculation of Induced Voltages in the Protected Cable
52 - 5.4.11 Conclusion
55 - SECTION 6 FIELD TESTS AND MEASUREMENTS
55 - 6.1 General
55 - 6.2 Safety Precautions
56 - 6.3 Testing Procedures
56 - 6.4 Elements of the Testing Circuit
59 - 6.5 Interpretation of Results
59 - 6.6 Ancillary Tests
60 - 6.6.1 Evaluation of Soil Resistivity
61 - 6.6.2 Determining Shielding Factors
62 - 6.7 A Practical Example
62 - 6.7.1 Details
63 - 6.7.2 Objects of the Tests
63 - 6.7.3 Lay-out of the Plant
65 - 6.7.4 Test Methods
66 - 6.7.5 Test Results
66 - 6.7.6 Discussion and Summary of Results
69 - 6.7.7 Further Action
70 - 6.7.8 Conclusions
76 - SECTION 7 RECORD OF POWER EARTH FAULTS
77 - SECTION 8 REFERENCES
79 - APPENDIX 1 - SHIELDING FACTORS OF EARTHED CONDUCTORS IN THE PROXIMITY OF TELECOMMUNICATION CABLES
79 - APPENDIX 2 - SHEATH RESISTANCE VERSUS EXTERNAL DIAMETER OF TELECOMMUNICATION CABLES
80 - APPENDIX 3 - SHIELDING FACTOR VERSUS SHEATH RESISTANCE OF TELECOMMUNICATION CABLES
81 - APPENDIX 4 - CONVERSION CHART FOR SHEATH RESISTANCE AND CONDUCTANCE
82 - APPENDIX 5 - SHIELDING FACTORS FOR LEAD-SHEATH CABLES
83 - APPENDIX 6 - SHIELDING FACTORS FOR PLASTIC-JACKET, LEAD-SHEATH CABLES
84 - APPENDIX 7 - SHIELDING FACTORS FOR MOISTURE-BARRIER CABLES
85 - APPENDIX 8 - SHIELDING FACTOR VERSUS DISTURBING FIELD
85 - (a) for 20/0.64 mm ST cable
85 - (b) for 20/0.90 mm ST cable
86 - (c) for 28/0.64 mm ST cable
86 - (d) for 50/0.64 mm ST cable
87 - (e) for 70/0.64 mm ST cable
87 - (f) for 100/0.64 mm ST cable
88 - (g) for GI pipes
88 - APPENDIX 9 - RESISTANCE VALUES FOR CONDUCTORS OF STANDARD SIZES
89 - APPENDIX 10 - LATENT REDUCTION FACTOR
90 - APPENDIX 11 - JOINT COMMITTEE FOR THE CO-ORDINATION OF POWER AND TELECOMMUNICATIONS SYSTEMS FAULT DOCKET
91 - APPENDIX 12 - ADDRESSES OF STATE POWER COORDINATION CONTACTS
92 - APPENDIX 13 - INDUCED VOLTAGES DUE TO TEST FAULT CURRENTS
92 - 1 SIGNIFICANCE OF THE PHASE ANGLE BETWEEN THE STANDING VOLTAGE AND THE MEASURED VOLTAGE WHEN THE POWER LINE IS EXCITED
93 - 2 DETERMINATION OF INDUCED VOLTAGE DUE TO TEST FAULT CURRENT

Provides guidance on the Code CJC 5, Low Frequency Induction (SAA HB101-1997, in sections dealing with the theory of LFI, calculations, determination of best engineering solution, evaluation of contributory and ameliorative factors, examples of calculations, field tests and measurements. Useful data is given in extensive appendices identical with the 1981 Telecom Australia/ESAA publication Application Guide for the Low Frequency Induction Code.

First published by Telecom Australia and ESAA 1981.
Reprinted 1984.
Reset and redesignated SAA HB102-1997 (CJC 6).
Incorporating: Amdt 1-1998