Basic Electrical Installation Work

| Kategorie: Kniha |

Strana 260 z 399

Jak získat tento dokument?

Poznámky redaktora

251 2.5 2.40 35 0.877 – 25 1.20 1.82 25 0.10 1 36.64 50 1.23 – 16 2.22 6 3.44 10 4.774 1.74 50 0.5 12.28 Reproduced from the IEE Site Guide kind permission the Institution Electrical Engineers.83 10 6. .454 2.66 16 1.5 7. Ω The total earth fault loop impedance therefore: ZS 702 202 .08 6 2.98 – 16 2.61 4 1. .5 12.91 10 3.727 1. given Table the Site Guide.5 30.048 1.5 14.674 2.5 24.911 1.20 1.71 4 2.20 25 2.5 19.51 2.02 4 9. this case the factor 1.5 25.07 35 1.20 and therefore the cable resistance under fault conditions will be: 0 585 702 .30 3.41 2.20 2.51 2.49 6 7.51 50 0.15 1. Ω.78 35 1.10 1.84 50 0.87 35 1.5 1.91 16 4.1 Table the IEE Site Guide: Value Resistance/Metre for Copper and Aluminium Conductors and per Metre 20°C in Milliohms/Metre Cross-sectional area (mm2 ) Resistance/metre (R1 R2)/ metre (mΩ/m) Phase conductor Protective conductor Copper Aluminium 1 18.Overcurrent, short circuit and earth fault protection 249 Table 12.5 10.82 4 4.557 – 25 1.387 0.69 6 6.16 10 1.5 16.524 0.5 1.114 1