Basic Electrical Installation Work

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65A may used safely rather than 52.Basic Electrical Installation Work 298 Therefore, cable capable carrying 27. Conductor size calculations The size cable used for installation depends upon: ● the current rating the cable under defined installation conditions and ● the maximum permitted drop voltage defined Regulation 525. Installed conditions: clipped surface installed with other cables trunking. 5.9V for lighting and 11. 2. Type cable: PVC, MICC, copper conductors aluminium conductors. Surrounding temperature: cable resistance increases temperature increases and insulation may melt the temperature too high. Type protection: for how long will the cable have carry fault current? Regulation 525 states that the drop voltage from the supply terminals to the fixed current-using equipment must not exceed for lighting circuits and for other uses the mains voltage. The cable rating, denoted It, may determined follows: It Current rating protective device Any applicable corre c ction factors .17A cable. The volt drop for a particular cable may found from: VD Factor Design current Length run The factor given the tables Appendix the IEE Regulations and Appendix the Site Guide. Where two cooking appliances are installed one room, such split-level cookers, one switch may be used control both appliances provided that neither appliance more than from the switch (On Site Guide, Appendix 8).3. They are also given Table 14. 3.5V for other uses 230V installation. Design current: cable must carry the full load current. The factors which influence the current rating are: 1. 4. That maximum 6. A cooking appliance must controlled switch separate from the cooker but readily accessible position