sec.23Design, installation and maintenance

### sec.23 Design, installation and maintenance The site senior executive for a coal mine must ensure the design, installation and maintenance of electrical equipment and installations at the mine provide for the following— reliable circuit interruption, under fault conditions, at all points in the mine’s electrical distribution system; each earthing system at the mine to be of sufficiently low impedance to ensure reliable operation of all electrical protection systems and devices and adequate protection against indirect contact; limiting prospective touch voltage, under fault conditions, to within acceptable limits; minimising potential impacts from voltage rise caused by lightning strike, static electricity, voltage surges and other transient voltages to within acceptable limits; preventing a person inadvertently contacting live parts of equipment or an installation exceeding extra low voltage. The design, installation and maintenance may provide for insulation or an enclosure, shield, interlocking device or automatic disconnection device for the equipment or installation. - (a) reliable circuit interruption, under fault conditions, at all points in the mine’s electrical distribution system; - (b) each earthing system at the mine to be of sufficiently low impedance to ensure reliable operation of all electrical protection systems and devices and adequate protection against indirect contact; - (c) limiting prospective touch voltage, under fault conditions, to within acceptable limits; - (d) minimising potential impacts from voltage rise caused by lightning strike, static electricity, voltage surges and other transient voltages to within acceptable limits; - (e) preventing a person inadvertently contacting live parts of equipment or an installation exceeding extra low voltage. Example for paragraph (e) — The design, installation and maintenance may provide for insulation or an enclosure, shield, interlocking device or automatic disconnection device for the equipment or installation.