The PU322 Series is a high-flow range of 3/2 way pneumatic solenoid valves designed for reliable directional control of single-acting pneumatic cylinders, actuators and pilot-operated pneumatic systems.
Available as normally closed PU322 or normally open PU322N versions, the range combines internal pilot operation with a robust anodised aluminium body, lockable manual override and large effective flow areas for demanding industrial pneumatic applications.
Available in 1/4", 3/8" and 1/2" BSP port sizes with effective flow areas from 18mm² to 70mm², the PU322 Series is ideal for industrial automation, OEM machinery, pneumatic control panels and general compressed air systems.
Valve Specification
Function:
3/2 way normally closed – PU322
3/2 way normally open – PU322N
Operation: Internal pilot
Port sizes:
1/4" BSP – PU322(N)-02-S
3/8" BSP – PU322(N)-03-S
1/2" BSP – PU322(N)-04-S
Optional threads: NPT or Rc
Effective orifice area:
1/4" – 18mm²
3/8" – 35mm²
1/2" – 70mm²
Operating pressure: 2 to 8 Bar
Proof pressure: 9.9 Bar
Body: Anodised aluminium alloy
Seals: NBR
Media: Compressed air
Ambient temperature: -10°C to +50°C
Manual override: Lockable
Mounting position: Any position
Coil & Electrical Specification
Power consumption: 4.5 Watts
Protection rating: IP65
Insulation class: Class F
Duty cycle: 100% continuous duty
Voltage tolerance: ±10%
Standard connection: DIN connector
Optional connection: Flying lead wire
Voltage Options
12VDC
24V DC
48VDC
24v AC
110V AC
220V AC
Other voltages available as options.
ATEX / IECEx Coil Option
Optional Nass Magnet System 8/22 explosion-protected solenoid operator available for hazardous area applications.
✓ Ex mb IIC T4 Gb
✓ Ex mb tb IIIC T130°C Db
✓ Zone 1 gas and Zone 21 dust
✓ ATEX Category 2G / 2D
✓ Gas Group IIC / Dust Group IIIC
✓ Protection rating: IP65
✓ 100% continuous duty
✓ Ambient: -20°C to +50°C
✓ ATEX: PTB 00 ATEX 2001 X
✓ IECEx: IECEx PTB 05.0006X
✓ ATEX Directive: 2014/34/EU
Valve Operation
PU322 – Normally Closed
In the normal de-energised position, the compressed air supply is closed.
When the solenoid is energised, internal pilot pressure shifts the valve spool to supply compressed air to the outlet port.
Removing electrical power allows the valve to spring return to its normally closed position.
PU322N – Normally Open
In the normal de-energised position, compressed air is supplied to the outlet.
When the solenoid is energised, internal pilot pressure shifts the valve spool and closes the air supply.
Removing electrical power returns the valve to its normally open position.
The lockable manual override allows valve operation during commissioning, machine setup, maintenance and fault diagnosis without electrical actuation.
Typical Applications
Single-acting pneumatic cylinders
Pneumatic actuators
Pilot air control
Industrial automation
OEM machinery
Packaging equipment
Assembly machinery
Process control systems
Pneumatic control panels
Machine automation
High-flow pneumatic systems
General compressed air installations
Quality & Reliability
The PU322 Series combines a high-flow internal pilot design with an anodised aluminium body and lockable manual override for reliable long-term pneumatic control.
