MRU-21

Earth Resistance Meter

Measurement methods

• 3-wire method – measurement of earthing systems using auxiliary probes
• 2-wire method – simplified measurement of resistance-to-earth
• Resistance of earth and compensatory conductors measured using current ≥200 mA with auto-zero function – meets the requirements of EN 61557-4

Additional features

• Measurement of resistance of auxiliary electrodes R_S and R_H
• Measurement of interference voltage
• Selection of maximum measuring voltage (25 V and 50 V)
• Auto-zero function for the resistance of measurement leads (R_CONT zero)

Application

MRU-21 is designed as a reliable measuring instrument, which is both technically advanced and easy to use. It is suitable for tests in industrial plants and in companies providing electrical measurement services. MRU-21 allows user to test individual earth electrodes and systems with multiple earthing electrodes.

Capabilities

Large and easy to read display shows the resistance values and supporting information in all weather conditions. Additional warnings inform the user about irregularities during the measurement.

Housing with IP54 rating ensures safety in difficult weather conditions and protect the device against splashes.

The results can be saved to the device’s memory. It is divided into 10 banks of  99 cells, each corresponding to one measurement. These results can be easily transferred to the Sonel Reader software for archiving or subsequent analysis and research.