Portable density and concentration meter - DMA 35 DMA 35 Ex DMA 35 Ex Petrol DMA 35 Ampere

Importance of the topic

Density and concentration measurement in field environments is vital for rapid quality control, process monitoring, and safety assurance across multiple industries including food, beverage, pharmaceuticals, chemicals and petroleum. Portable instruments like the DMA 35 series enable on-site determinations that replace glass hydrometers, minimize sample handling and accelerate decision-making at critical control points.

Objectives and overview of the article

This document presents the features, performance and applications of the DMA 35 family of portable density and concentration meters by Anton Paar. Four versions are covered: the standard DMA 35, the intrinsically safe DMA 35 Ex and Ex Petrol for hazardous areas, and the DMA 35 Ampere for sulfuric acid monitoring in lead–acid batteries. The goal is to illustrate how these devices deliver accurate, traceable measurements in the field.

Methodology

The instruments employ the oscillating U-tube principle to determine density, specific gravity, and derived concentration values. A sample volume of just 2 mL is drawn into the U-shaped borosilicate glass tube using a manual pump or syringe. Viscosity effects are automatically corrected, and gas bubbles are expelled by strategic oscillator placement to ensure measurement integrity.

Instrumentation

• Oscillating U-tube sensor made of borosilicate glass
• Capacitive keys and gesture control interface
• Integrated pump for rapid sample filling
• Rotating, high-contrast display with hard-glass protection
• RFID reader for sample identification and method selection
• Bluetooth interface for data export
• Replaceable measuring cell with patented quick-change design
• ATEX and IECEx certification for Ex and Ex Petrol versions (II 2G Ex ib IIB T4 Gb)
• IP54-rated housing to resist dust and water splashes

Main results and discussion

The DMA 35 series achieves density measurements from 0 g/cm3 to 3 g/cm3 with an accuracy of ±0.0005 g/cm3 and temperature readings within ±0.2 °C. Repeatability and reproducibility meet ISO 5725 standards. Measurement time is a few seconds, and sample intake is up to ten times faster than comparable devices. Data management features allow storage of 1200 results, 250 sample IDs and 30 methods, ensuring full traceability and error avoidance.

Benefits and practical applications

• Rapid on-site results without sample transport to the laboratory
• Minimal sample consumption preserves valuable or hazardous liquids
• Intrinsic safety for flammable environments in chemical and petroleum industries
• Versatility across sectors: monitoring beer fermentation, sugar content in juices, alcohol in spirits, density of dairy products, pharmaceutical solutions, cooling agents and more
• Data integrity via RFID and digital export supports quality assurance and regulatory compliance

Future trends and potential applications

Integration with cloud platforms and IoT networks will further streamline data workflows and enable real-time process feedback. Advances in sensor miniaturization and multi-parameter detection may expand on-site analytics to viscosity, refractive index and more. Enhanced software for predictive maintenance and process optimization can leverage the digital architecture of the DMA 35 series.

Conclusion

The Anton Paar DMA 35 family offers a robust, accurate and user-friendly solution for portable density and concentration measurements. Its intrinsic safety, low sample requirement and digital connectivity make it a valuable tool for quality control and process monitoring in diverse industrial settings.