PAS**/A type compressor units comply with the requirements of European Directive 2014/34/UE (ATEX) for the I group of equipment of M2 category that can be applied in underground excavations of coal mines threatened with methane and coal dust explosion. PAS**/A type compressor units can be applied in bad ventilated excavations or at considerable depths in underground coal mines where keeping good climatic conditions complying with binding regulations makes problem for ventilating services. All groups of PAS**/A type compressor units are designated for local power supply of equipment with pneumatic drive, pipelines and air-water installations with spraying system applied in combined cutter loaders.
The design of PAS**/A type compressor units is based on screw compressing set. The compressor units are air cooled but in case of their location in bad ventilated places or with high ambient temperature there is the possibility to make the equipment with additional water cooled oil cooler making use of water from fire-fighting water pipeline. Compressor units are built in solid container furnished with runners and grips for any kind of means of transportation. The width of PAS**/A type compressors is maximum 1000 meters and that makes their transportation and positioning easier in coal mine gallery. The compressors units are furnished with automated control system providing their safe operation without necessity of permanent service. The control of compressor unit is performed by use of the starter being the integral part of the equipment. The starters are furnished with protection devices against the effects of: excessive rise of temperature of winding in motor, short-circuits, overloads, current and voltage asymmetry, excessive symmetric voltage supply reduction, improper sequence of phases and excessive reduction of insulation resistance.