Answer:Fruitland® rotary vane vacuum pumps are capable of achieving very high vacuum levels, up to 95% or 28.5” HgV at sea level. Factors effecting the vacuum level of the pump are speed (RPM), elevation (your location) and pump temperature. Please remember that at higher vacuum and speed and longer running time, more heat is generated. For good wear life, vacuum pumps are recommended to be operated below the maximum allowable speed (1400 RPM) and temperature (375°F Exhaust). Vacuum and pressure relief valves are generally set by the end-user based upon their own requirements and recommendations from the tank builders.
However the following guidelines are also recommended. For short intermittent duty (5 to 10 min), the pump can be operated at very high vacuum, up to 27” Hg, and pressure up to 25 psi, while keeping a close eye at temperature rise of the exhaust air, not to exceed 375°F. Please check the integrity (age) of your system and limitations from the tank builders before operating at higher rate. It is up to the operator of the pump to set the vacuum and pressure relief valves to suit the application. For continuous duty the relief valves can be set at 5″ to 15″ psi* for pressure and 15″ to 22” Hg for vacuum. However there can be slight deviations from these limits based on your application, location and atmosphere.
*IMPORTANT NOTE: Pressure above 7 psi is not recommended unless the tank and system has the appropriate certification.