Jones Quarry crushed aggregate used for insulation of ground surface layers on Transpower substation switchyards – an integral part of safety in switchyards.

Jones Quarry switchyard crushed rock aggregate complies with Transpower Specification TP PS 52.04, and is paramount to safety.

The purpose of using Jones Quarry crushed rock aggregate in insulating surface layers in substation switchyards is to reduce the body currents that could flow through personnel if they are in contact with metal objects such as structures, or equipment tanks etc. when system earth faults occur.

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Thermal sand is now widely used when installing underground cables. The thermal sand is rated or tested to provide a known heat transfer efficiency. The cable and the thermal sand are installed so that the thermal sand is in direct contact with the cable. The thermal sands high heat transfer efficiency ensures the heat generated by the cable is transferred from the cable through the thermal sand to the surrounding earth.