Ensure grid voltage and fan motor rated voltage consistent with megger, check the motor winding insulation value BK54 main fan, should be more than 50MΩ before use. Exhaust ventilation due to the negative pressure ventilation DK40 is the main fan, fan stopped once, underground air pressure will be slightly increased, the amount of gas emission will be reduced, the role of inhibition of gas; K45 main fan | Explosion Main Fan (certified) | Yantai Main Ventilator Co. provided by Zibo Blower. Zibo Blower Factory Co., Ltd. (www.zibo-fengji.com) is an industry leader in Shandong Zibo, fans, ventilation equipment, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Zibo Blower leadership with the staff warmly welcome all inquiries negotiations to create a better future Zibo Blower.