MRU-30
Index: WMGBMRU30
Earth Resistance and Resistivity Meter
Description
Technical Specification
Files
  • Description

    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.

    Virtual instrument application of Sonel MRU-30

  • Technical Specification

    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 measuring multiple earthing without underground connections.
    • 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,
    • measurement 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.
  • Files

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