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Tuesday, 16 August 2016

Electricity Rules for Earthling

Electricity Rules for Earthling Points : electricity rules for earthling, connection with earth of a multi-wire system, connection with earth of concentric conductors, Connection with Earth of Frames of Generators The frame of every generator, stationary motor, and so far as is practicable, portable motor, and the metallic parts (not intended as conductors) of all transformers and regulating of controlling apparatus connected with the supply shall be earthed by the owner by two separate and distinct connection with earth. Connection with Earth of a Multi-Wire System In every distributing system in which there is a neutral conductor, where the pressure between the neutral conductor and an outer or phase conductor exceeds 125 volts, the neutral conductor shall be connected with earth by two separate and distinct connections from the neutral bus-bar atid in accordance with the following provisions, namely.

a) The connection shall be made at one point only on each distinct system, namely, at the generating stations or sub-stations, or both, as the case may be, and the insulation of the system shall be maintained.

(b) The connection shall not be contracted with any water-main, gas main or similar main. As the case may be, a resistance, no exceeding 20 ohms, may be inserted between the neutral bus-bar and earth. if so inserted, it shall be of sufficient cross-sectional area to carry the current which would pass should an outer or phase conductor become accidentally connected with earth.

(c) The connection shall not be removed except for the purpose of testing, in which case it shall be made good again as soon as such test is finished. A record of any such disconnection shall be kept.

(d) The connection shall not be removed except between I a.m. and 3. a.m., and the generator is in operation energy is being used.

(e) The current from the neutral conductor to earth shall direct current distributing system, .be continuously recorded) if at any time it exceeds one-thousandth parts of the maximum supply current, steps shall immediately the maximums supply current, steps shah immediately be taken to improve the insulation of the system.
Connection With Earth of Concentric Conductors (1) Notwithstanding anything contained in sub-rule (4) of rule 49, when concentric conductors are used, the owner shall maintain the insulation throughout, except that the external conductor may be connected with earth at one point. Provided that where a person generates electricity exclusively for use on his own premises, he may use a bare external conductor if it is connected with earth and if no switch, cut-out or circuit breaker is inserted in that conductor or in any conductor connected thereto. Exception Switches, cut-outs or circuit breakers may be used to break the connection with the generators or transformers supplying energy. Provided that in no case shall the connection of a bare external conductor with earth be thereby broken.

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