Positive: Merry absolute pressure (pressure) is greater than the outer wells or duct elevation outside the same atmospheric pressure (pressure) Hotels blower relative pressure (pressure) is positive, said the positive working conditions [1], the power supply. Three-phase 380v, 50Hz 2, temperature. -20-60 ℃ 3, humidity <90% 4 medium dust content ≤100mg / m3 blower samples, rich ventilation equipment (certified), the blower is provided by Dezhou Plumper ventilation plant. Dezhou Plumper ventilation plant (www.frtfsb.com) is a leader in Dezhou, fans, ventilation equipment, over the years, the company implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Rich ventilation equipment in leadership with the staff warmly welcome all inquiries negotiations to create rich, ventilation a better future.