MRU-30
Earth Resistance and Resistivity Meter
- Description Specs Details Overview Components Packages Resources Additional Modules Complementary products Architecture Tools Benefits Features Customer Ordering
- Thông số Specs Details Overview Components Packages Resources Additional Modules Complementary products Architecture Tools Benefits Features Customer Ordering
The Sonel MRU-30 uses most known methods of earth resistance measurements. Tests can be performed using the 3-pole, 4-pole, 3-pole with auxiliary clamp and also, additionally, the MRU-30 employs the two clamp method of measurement, without the use of auxiliary test rods which can’t be used in some situations. Complementary features of the MRU-30 are measurements of soil resistivity, continuity measurement of protective and equipotential conductors and, using clamps, leakage currents and interference voltages.
- Robust and weatherproof (IP65) – no ingress of dust, water protected by a nozzle against enclosure from any direction.
- Ergonomic casing – small and handy casing to make the measurements more convenient than before.
- Built-in rechargeable battery – saving time to replace flat batteries; can be recharged from Power Bank and Cigarette Lighter Socket!
- Clear on-screen notes – displayed on screen before and after the measurement to alert user of possible dangers and irregularities.
- Many measurement methods available in a small, portable casing.
It allows to take the measurements of:
- earthing resistance using auxiliary electrodes,
- earthing resistance using auxiliary electrodes and clamp (for measurements of multiple earthing),
- earthing resistance using double clamps (for measurement of earthing when it is impossible to use auxiliary electrodes),
- ground resistivity (Wenner method),
- continuity of equipotential bondings and protective
- conductors (meeting the requirements IEC 60364) with auto-zero function – with current 200mA.
Additionally:
- measurement of resistance of auxiliary electrodes RS and RH,
- measurement of interference voltage,
- measurement in the presence of interference voltage in the power network
- with frequency 50Hz, 60Hz,
- selection of maximum measuring voltage (25V and 50V),
- introducing the distance between the electrodes for the resistivity in metres (m) and feet (ft),
- memory of 990 measurements (10 banks of 99 cells each),
- calibration of clamp used,
- data transmission to the computer (USB),
- indication of battery state.
Measurement of interference voltage UN (RMS)
| Range | Resolution | Accuracy |
| 0…100 V | 1 V | ±(10% m.v. + 1 digit) |
Measurement of continuity of equipotential bondings and protective conductors (Rcont)
measurement range to IEC 61557-4:2007: 0,13 Ω…1999 Ω
| Range | Resolution | Accuracy |
| 0,00…9,99 Ω | 0,01 Ω | ±(2% m.v. + 3 digits) |
| 10,0…99,9 Ω | 0,1 Ω | |
| 100…1999 Ω | 1 Ω |
• measurement current: under short circuit >200mA
• frequency of measurement current: 125 Hz (for networks 50 Hz) and 150 Hz (for networks 60 Hz)
Measurement of earthing resistance (method 3- and 4-pole)
measurement range to IEC 61557-5:2007: 0,53 Ω…9999 Ω (dla 50 V)
| Range | Resolution | Accuracy |
| 0,00…19,99 Ω | 0,01 Ω | ±(3% m.v. + 3 digits) |
| 20,0…199,9 Ω | 0,1 Ω | |
| 200,0…1999 Ω | 1 Ω | ±5% m.v. |
| 2000…9999 Ω | 1 Ω | ±8% m.v. |
• measurement current: under short circuit >20 mA,
• voltage on open terminals: selectable 25 V AC or 50 V AC,
• frequency of measurement current: 125 Hz (for networks 50 Hz) or 150 Hz (for 60 Hz).
Measurement of multiple earthing esistance with using the clamp and auxiliary electrodes (3p + clamp)
| Range | Resolution | Accuracy |
| 0,00…19,99 Ω | 0,01 Ω | ±(3% m.v. + 3 digits) |
| 20,0…199,9 Ω | 0,1 Ω | |
| 200…1999 Ω | 1 Ω | ±5% m.v. |
| 2000…9999 Ω | 1 Ω | ±8% m.v. |
• voltage on open terminals: selectable 25 V AC or 50 V AC,
• measurement current: under short circuit >20 mA,
• frequency of measurement current: 125 Hz (for networks 50 Hz) and 150 Hz (for networks 60 Hz)
Measurement of resistance of auxiliary electrodes RH i RS
| Range | Resolution | Accuracy |
| 0…999 Ω | 1 Ω | ±(5% m.v.+ 8 digits) |
| 1,00k…9,99 kΩ | 0,01 kΩ | |
| 10,0k…19,9 kΩ | 0,1 kΩ |
Measurement of multiple earthing resistance with using double clamps
| Range | Resolution | Accuracy |
| 0,00…19,99 Ω | 0,01 Ω | ±(10% m.v. + 8 digits) |
| 20,0…99,9 Ω | 0,1 Ω | ±(20% m.v. + 3 digits) |
• frequency of measurement current: 125 Hz (for networks 50 Hz) and 150 Hz
(for networks 60 Hz)
Measurement of ground resistivity
Measurement method: Wenner, ρ=2πLRE
| Range | Resolution | Accuracy |
| 0,00…9,99 Ωm | 0,01 Ωm | depending on measurement accuracy RE with 4p method, but not less than ±1 digit |
| 10,0…99,9 Ωm | 0,1 Ωm | |
| 100…999 Ωm | 1 Ωm | |
| 1,00…9,99 kΩm | 0,01 kΩm | |
| 10,0…99,9 kΩm | 0,1 kΩm | |
| 100…999 kΩm | 1 kΩm |
L – distance between probes: 1…50 m.. or 1…150 ft
Electric security:
- type of insulation: double, according to EN 61010-1 i IEC 61557,
- mesurement category: CAT III 300V wg EN 61010-1,
- protection class acc. to EN 60529: IP65,
Rated operational conditions:
- operation temperature: -10…+55°C,
- storage temperature: -20…+80°C,
- humidity: 20…90%,
Other technical data:
- LCD display: segment, backlit,
- dimensions: 200x150x74 mm.
