PSIEV-series industrial grade dual-stage vacuum pumps are designed for reliable, continuous operation. They have a balance between low cost and high performance.
They come with gas ballast, which is designed purposefully to pull a less deep slower vacuum. By opening the gas ballast, it allows dry air to go directly into the pump diluting the vacuum pull. It also helps keep moisture, solvents, and other contaminants from getting into the pump, and instead passes it through to the exhaust. The built-in check valve prevents pump oil back-flow reducing contaminates from entering the vacuum system.
It is important to note that pumps should always be ran in a well ventilated area.