PRO 921/ PRO 925 Multiparameter

Features:

✔ Thermocouple input e. g. for Type K surface probes

✔ Backlit dot matrix/clear text display, multilingual

✔ Life chart display

✔ Data logger with files read out via USB (PRO 925 only)

✔ Foldable stand and magnet for flexible operation

✔ IP 67 waterproof, except TC inputs

✔ Optionally available DAkkS/ ACCREDIA certificate

The PRO 921/925 are high class professional multiparameter handheld meters with a rich set of features, high grade robustness and operating comfort for safe and reliable use in HVAC applications. PRO 925 have data logging capabilities. Drop and impact protection is making it a perfect choice for field use, integrated pop-up stand helps in laboratory use.

Description

PRO 92x – Mulitfunctional instrument for DX – digital sensors with type K inputs

The PRO 921/ PRO 925 Multiparameter are high class professional multiparameter handheld meters with a rich set of features, high grade robustness and operating comfort for safe and reliable use in HVAC applications.
PRO 925 have data logging capabilities. Drop and impact protection is making it a perfect choice for field use, integrated pop-up stand helps in laboratory use.
The combination of thermocouple inputs for use of economic thermocouple probes and the digital input for long connection of sensors out of the DX-Sensors portfolio is an innovative combination to suit practical requirements of combined measurements like surface or difference temperature and pressure (HVAC) or surface temperature and climate/humidity (building and energy measurement).

The PRO 921/ PRO 925 Multiparameter are compact, rugged, and easy-to-use multiparameter handheld meters designed for accurate water quality analysis in field and laboratory environments. These devices can simultaneously measure critical parameters such as pH, conductivity, total dissolved solids (TDS), salinity, temperature, and dissolved oxygen (DO) (PRO 925 only), offering a reliable and convenient solution for environmental monitoring, aquaculture, wastewater treatment, and research applications.

Both models are equipped with automatic temperature compensation (ATC), intuitive interface, LCD backlit display, and support for multi-sensor probes—making them a powerful tool for professionals needing portable, multipoint data collection.

Features:

All-in-One Measurement
Measures pH, conductivity, TDS, salinity, temperature (and DO in PRO 925).
Interchangeable Multi-Probe Design
Compatible with smart sensors; quick replacement and calibration.
Automatic Temperature Compensation (ATC)
Ensures consistent results across varying field conditions.
Data Logging & USB Transfer
Stores readings internally with easy export for documentation and analysis.
Smart Calibration Memory
Remembers calibration data per sensor—no rework needed.
Field-Ready Design
Waterproof, lightweight, with long battery life for on-site measurements.

Applications:

Surface and Groundwater Quality Monitoring
Wastewater Treatment Plants
Aquaculture and Fisheries
Agriculture and Irrigation Water Testing
Industrial Effluent Monitoring
Environmental Research and Education

Technical Data

Technical Specifications

Storage capacity

only PRO 925: Up to 1 million data sets, file system based
Each data set includes date/timestamp and measurement.
Data are stored in CVS files.

Power supply

4 x AA cells (incl. in scope of delivery)
External 5 V DC via USB C (power adapter or PC USB port)

Logging type

only PRO 925: Automatic with manual start/stop

Measurement rate

1 meas/s

Weight

370 g incl. battery

Power consumption

10 mA typ. (excluding probes)

Operating conditions

-5 ... +50 °C; 0 ... 95 % RH (non-condensing)

Storage temperature

-25 … 65 °C (without batteries)

Dimensions

170 x 78 x 38 mm

APPLICATIONS

The PRO 921/925 multiparameter handheld meters are designed for a wide range of professional applications where precise measurement and data logging are essential:

- HVAC System Monitoring:
  Measure and log temperature, humidity, pressure, and air quality parameters for heating, ventilation, and air conditioning system diagnostics and commissioning.
- Building and Energy Audits:
  Simultaneously monitor surface temperature, climate/humidity, and differential temperatures to assess building insulation, detect thermal bridges, and optimize energy efficiency.
- Industrial Process Control:
  Use interchangeable DX-series digital probes to monitor critical parameters in industrial environments, supporting process optimization and quality assurance.
- Laboratory and Research:
  High accuracy and robust design make the PRO 921/925 ideal for laboratory measurements, experiments, and long-term data collection.
- Field Service and Maintenance:
  Portable, impact-resistant construction and IP67 protection (except TC inputs) make these meters suitable for demanding fieldwork, including equipment maintenance and troubleshooting.
- Environmental Monitoring:
  Combine temperature, humidity, and air quality probes to monitor environmental conditions in greenhouses, storage facilities, and sensitive production areas.
- Data Logging for Compliance:
  The PRO 925’s data logger stores up to 1 million data sets with date/time stamps, supporting regulatory compliance and detailed reporting in various industries.