Structural composition The cement fineness negative pressure sieve analyzer is mainly composed of sieve base, micro motor, dust collector, cyclone and electrical control. instructions 1. before sieving test, adjust the digital explicit time relay, set it at 120s, put the negative pressure sieve on the screen seat, cover the sieve cover, turn on the power supply, adjust the negative pressure to -4000~-6000pa range, then turn off the machine. 2. Weigh 25g of sample, put it into a clean negative pressure screen, cover the screen cover, start the instrument again and screen continuously. During this period, if a sample is attached to the screen cover, tap the screen cover gently to make the sample fall. When the screen is full for 120s, the instrument will stop automatically. 3. After screening, weigh the residue with a balance matters needing attention 1. Regularly pour out the cement in the dust collecting bottle. 2. If the negative pressure cannot meet the requirements of the national standard (- 4000 ~ - 6000pa) after using for a period of time, please clean the dust collection bag in the vacuum cleaner. 3. The vacuum cleaner shall not work continuously for more than 15 minutes, otherwise it is easy to overheat and burn out.