Page 216 - Handbook of Electrical Engineering
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200    HANDBOOK OF ELECTRICAL ENGINEERING

              also the IEE Wiring Regulations in its sixteenth form. Such tables cover a wide range of installation
              configurations and environmental conditions, not all of which are applicable in the oil industry.
              The following tables were compiled to be on similar bases and for installations commonly used in
              the oil industry. For example all the reactance data are given for a frequency of 50 Hz. The con-
              ductor temperatures are those suitable for the insulation where rated current follows in the cable.
                                                                                ◦
              The resistance data of the armouring has been given at a temperature of 80 C for wire armour-
                        ◦
              ing and 60 C for braided armouring so that the earth loop impedance can be calculated under
              fault conditions. The depth of burial of cables is taken to the 0.5 m and the ground temperature
                ◦
              15 C. They should be used as guidance in estimating cable sizes. When calculations are being
              finalised for a project then the data from a particular manufacturer should be used. Most of the
              data presented were kindly made available by the Anixter Wire and Cable group of companies,
              see Reference 6. Reference 4 also provides comprehensive data on many types of cables, and was
              used as a source for PVC insulated cables. Reference 7 although somewhat dated is also a valuable
              source of data.



                                    Table 9.11. Summary of cable rating and data tables
                             Table       Cable                Brief description
                                      voltage grade
                                                      Land based installations:
                             9.12     600/1000 V      PVC insulation
                                                      Current ratings of 1-core cables
                             9.13     600/1000 V      PVC insulation
                                                      Impedance data in ohms/km
                             9.14     600/1000 V      PVC insulation
                                                      Current ratings of 3 & 4-core cables
                             9.15     600/1000 V      XLPE insulation
                                                      Current ratings of 1-core cables
                             9.16     600/1000 V      XLPE insulation
                                                      Impedance data in ohms/km
                             9.17     600/1000 V      XLPE insulation
                                                      Current ratings of 3 & 4-core cables
                             9.18     3800/6600 V
                                      6350/11,000 V   XLPE insulation
                                      8700/15,000 V   Current ratings of 1-core cables
                             9.19     3800/6600 V     Impedance data in ohms/km
                             9.20     6350/11,000 V   Impedance data in ohms/km
                             9.21     8700/15,000 V   Impedance data in ohms/km
                                      3800/6600 V
                             9.22     6350/11,000 V   Current ratings of 3-core cables
                                      8700/15,000 V
                                                      Marine installations:
                             9.23     600/1000 V      EPR insulation
                                                      Current ratings of 1, 3 & 4-core cables
                             9.24     600/1000 V      Impedance data in ohms/km
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