Code of Practice for the Electricity (Wiring) Regulations - 2009 Edition
Code of Practice for the Electricity (Wiring) Regulations - 2009 Edition
Code of Practice for the Electricity (Wiring) Regulations - 2009 Edition
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Appendix 6<br />
Current Carrying Capacities and Voltage Drop Tables <strong>for</strong><br />
PVC Insulated and XLPE Insulated Cables<br />
(Note: 1. For cable types o<strong>the</strong>r than PVC insulated or XLPE insulated cables,<br />
tables <strong>of</strong> current carrying capacities and voltage drop can be<br />
obtained in BS 7671.<br />
(Note: 2. PVC insulated cables are also known as 70°C <strong>the</strong>rmoplastic<br />
insulated cables.<br />
(Note: 3. XLPE insulated cables are also known as 90°C <strong>the</strong>rmosetting<br />
insulated cables.)<br />
1. Tables <strong>of</strong> current carrying capacities<br />
(a) The tabulated current carrying capacities relate to continuous loading<br />
<strong>of</strong> cables in single circuit with <strong>the</strong> installation methods shown in<br />
Appendix 7. The values correspond to <strong>the</strong> conductor operating<br />
temperatures indicated in <strong>the</strong> headings <strong>of</strong> <strong>the</strong> tables and <strong>for</strong> a.c.<br />
operation apply only to frequencies in <strong>the</strong> range 49 to 61 Hz.<br />
(b) The values <strong>of</strong> current tabulated represent current carrying capacities<br />
where no correction factor is applied. Under individual installation<br />
conditions, appropriate correction factors (see Appendix 5) <strong>for</strong> ambient<br />
temperature, grouping and <strong>the</strong>rmal insulation etc. should be applied as<br />
multipliers to <strong>the</strong> tabulated values.<br />
2. Tables <strong>of</strong> voltage drop<br />
(a) In <strong>the</strong> Tables, values <strong>of</strong> voltage drop are given <strong>for</strong> a current <strong>of</strong> one<br />
ampere <strong>for</strong> a metre run and represent <strong>the</strong> result <strong>of</strong> <strong>the</strong> voltage drops in<br />
all <strong>the</strong> circuit conductors. The values <strong>of</strong> voltage drop assume that <strong>the</strong><br />
conductors are at <strong>the</strong>ir maximum permitted normal operating<br />
temperatures. For a.c. operation, <strong>the</strong> tabulated values apply only to<br />
frequencies in <strong>the</strong> range 49 to 61 Hz and <strong>for</strong> armoured cables, <strong>the</strong> values<br />
apply where <strong>the</strong> armour is bonded.<br />
(b) For cables having conductors cross-sectional area <strong>of</strong> 16 mm2 or less,<br />
inductance can be ignored and only <strong>the</strong> resistive component (mV/A/m),<br />
values are tabulated. For cables having conductors cross-sectional area<br />
greater than 16 mm2 , <strong>the</strong> impedance values are given as (mV/A/m)z,<br />
toge<strong>the</strong>r with <strong>the</strong> resistive component (mV/A/m)r and <strong>the</strong> reactive<br />
component (mV/A/m)x.<br />
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