These devices control the level of vacuum, maintaining it constant at the pre-set value (secondary vacuum), regardless of the network’s flow rate and the fluctuations in vacuum level (primary vacuum).
They operate by membrane-piston and exploit the pressure differential between the secondary vacuum and the atmospheric pressure.
Unlike the vacuum control valves, reducers do not release air into the circuit, thereby allowing for the creation more grip points taken at different degrees of vacuum, from a single vacuum source.
The level of vacuum is adjusted manually by turning the knurled thumb screw clockwise to increase it, and counter clockwise to decrease it.

Technical features
- Operation: membrane-piston regulator
- Adjustable operating pressure: from 800 to 1 mbar abs.
- Flow rate : from 390 to 750 m3/h.
- Room temperature: from -10 to +80 °C
- Installation position: any

Usage
The best use of vacuum reducers is in centralised plants where, regardless of the plant’s level of vacuum, each outlet can be adjusted within that value. Moreover, they are necessary whenever the working vacuum must be lower than the primary vacuum.