... of transformer in coal mines, which are hazardous for gas (methane) and/or coal dust, and also for protection from short circuit ... adjusted Explosion protected mine starter, Coal mine explosion proof or flame proof starter QJZ2-200,315,400 Verified Information This ... of Explosion Proof Electric Appliances, Explosion Proof Lamps, Manufacture of Gas Meter and Electric Instrument 2012/03/20 --- 2015/03/19 ...