The PAMAS S4031 is a portable particle counter for liquids. It is used for research and standard measurements in laboratories and test institutes and is adequate for indoor and field applications. The instrument can be applied for batch sampling or for online measurements. A wear resistant ceramic piston pump guarantees a constant flow. With a simple-to-use touch screen user interface, operation is easy and intuitive. Up to 32 free adjustable size channels may be selected and stored in the system. The system is equipped with an integrated battery for more than 3 hours operation and data storage of more than 4000 measurements. Real time sample measurement data can be printed during the analysis and also be revisited and printed at anytime at a later date.

Product features

  • Robust & convenient design

  • Lightweight only 8kg

  • Customizable measurement analysis settings

  • Intuitive operation via touch screen

  • Automatic sample flow and volume control by wear resistant ceramic piston pump

  • 32 freely adjustable size channels

  • Measurement from pressureless up to 6 bar/420 bar system pressure, depending on the version

  • Use of any sample vessel

  • Internal data storage of more than 4,000 measurements

  • Display of actual and saved measurement results and printed via integrated thermo printer

  • Same measurement accuracy as a laboratory unit

  • Multilingual menu navigation

  • Battery running time of more than 4 hours


  • Water

  • Suspensions

  • Cleaning fluids

  • Sea and brackish water

  • Corrosive fluids

  • Hydraulic Oil

  • Turbine and insulation oils

  • Gear and motor oils

  • Fuels

  • Phosphate ester based hydraulic fluids

  • Water based hydraulic fluids

Volumetric sensors

Available size ranges:

  • 4–70 µm(c) (IS1–200 μm (ISO 21501-3)O 11171)

  • 4–70 μm(c) (ISO 11171)

  • 2–100 μm (ISO 4402)

    Max. particle concentration: 24,000 P/ml* at 25 ml/min**

Available size ranges:

  • 1–200 μm (ISO 21501-3)

  • 1–100 μm (ISO 4402)

  • 4–70 μm(c) (ISO 11171)

    Max. particle concentration: 120,000 P/ml* at 25 ml/min** Other sensors for larger particle sizes or higher concentrations are available on request.


  • PAMAS S4031 Standard for aqueous liquids

  • PAMAS S4031 Seawater for Saline and brackish water

  • PAMAS S4031 CL for corrosive liquids

  • PAMAS S4031 Oil at up to 420 bar system pressure

  • PAMAS S4031 Lube Oil for highly viscous oil up to 1,000 cSt

  • PAMAS S4031 Fuel for fuels such as petrol, diesel or kerosene

  • PAMAS S4031Skydrol for phosphate ester based hydraulic fluids

  • PAMAS S4031 WG for water based hydraulic fluids


All versions are optionally available in the robust PAMAS GO housing.

Standards and methods
ISO 11171 ISO 4402 ISO 4406 SAE AS4059 NAS 1638 GOST 17216
GJB 420B
GJB 420A
NAVAIR 01-1A-17*
SAE 749D*
ISO/DIS 11218.2*
ASTM D7647
IEC 60970
ASTM D6786
ISO 11500

* in connection with PAMAS PMA software.