Series NL4
Maintenance units and components
The Aventics Series NL4 specialises in combined filter-pressure regulators (NL4-FRE) and 2-part maintenance units (NL4-ACD) for G 1/8 to G 3/4 port connections. With operating pressures up to 10 bar and a control range up to 100 bar, the NL4-FRE combines a particle filter (5 µm) and pressure regulator in a compact housing that significantly reduces the space requirement compared to a separate FRL chain.
NL4-FRE filter-pressure regulators are available in G 1/8 and G 3/4 with various bowl materials (SSS, PBS, PNB) and drain types (HO manual, AO automatic). NL4-ACD 2-part units also combine filter and regulator and are available in the same port sizes and filter fineness grades, complemented by a regulator with GAU (upward gauge port).
| Type | Function | Port / Key feature |
|---|---|---|
| NL4-FRE | Filter-pressure regulator | G 1/8-G 3/4; control range GAN/GAU up to 100 bar; 5 µm; SSS/PBS/PNB |
| NL4-ACD | 2-part maintenance unit | G 1/8-G 3/4; filter + regulator GAU; PBS/SSS/PNB; HO/AO |
NL4-FRE is the right choice when filtration and pressure regulation must be combined at a single mounting point. The basic type (GAN, no gauge port) suits applications without continuous pressure monitoring; the GAU type with upward-facing gauge port allows direct mounting of a pressure gauge or switch. For bowl selection: SSS for aggressive media and corrosive environments, PBS with sight glass for visual condensate-level checks, PNB for standard applications without a guard. Automatic drain AO is recommended where frequent condensate accumulation or unattended operation is expected.
Typical applications: Space-saving compressed-air preparation at individual workstations and handling units, pressure regulation for pneumatic cylinders and valve groups in packaging machines, retrofit at existing G 1/8 to G 3/4 compressed-air points where space is limited, and supply of pneumatic control units and switching valve groups in general manufacturing automation.