Coal mine high voltage energy storage power supply requirements and standards

What voltage is used in underground coal operations?

Underground coal operations use mining machinery powered at 3.3 kV. High voltage practices and procedures must be used on these circuits, it is not acceptable to plug and unplug restrained plugs at 3.3kV, without effecting “whole current” isolation. For high voltage distribution systems a “permit to work” system must be used and records kept.

What voltage is used in mining?

Where mining operations are concerned, in the vast majority of cases the voltage will be 20 to 35 kV, which meets the needs of most mines with respect to both consumption and distance. The next step, power distribution to the loads, involves the first voltage transformation down to 6 kV.

Should a 6 kV system be used in a mining operation?

The general conclusion is that, in a typical mining operation, a 6 kV system will cover practically all the immediate requirements of the major loads and of the pit supply network, for which, moreover, standard equipment is readily available.

What is a power supply for a mining operation?

The concept of power supply for a mining operation, therefore, is one which provides for a reliable supply to the main distribution point in a mine, from which power is then distributed to all the key loads in the operation.

How many high-voltage continuous mining machines are there?

There are 27 high-voltage continuous mining machines in the 8 underground coal mines that have been granted PFMs. Some of the requirements in this final rule are not included in those PFMs.

What if a coal operation does not use high voltage practices?

Where a coal operation chooses to not use accepted (mining and non-mining industry) high voltage practices on circuits whose nominal voltage exceeds 1000 V and is less than 1200V, this must be supported by a risk assessment and nominated controls, including specific procedures to prevent electric shock, arcing and failure of explosion protection.