MRU-120  

Catalog index: WMGBMRU120

Earth Resistance and Resistivity Meter

 

      

Possible measurements:

  • earth resistance measurment with 3-pole,4-pole method,
  • earth resistance measurement without disconnecting measured earths (using clamp),
  • continuity of equipotential bondings and protecting conductors
  • two clamps earth resistance measurement without auxiliary test probs,
  • earth resistivity measurement

It allows to take the measurements of:

  • earth resistance using auxiliary electrodes,
  • earth resistance using auxiliary electrodes and clamp (for measurements of multiple earth)
  • earth resistance using double clamps (for measurement of earthing when it is impossible to use auxiliary electrodes),
  • ground resistivity (Wenner method),
  • measurement of continuity of equipotential bondings and protective conductors (meeting the requirements of IEC 60364 – 6-61:2000 section 6.12.2) with auto-zero function – with current 200 mA.

Additionally:

  • measurement of resistance of auxiliary electrodes RS and RH,
  • measurement of interference voltage,
  • measurement of interference frequency,
  • measurement in the presence of interference voltage in the power network with frequency 50 Hz, 60 Hz
  • selection of maximum measuring voltage (25 V and 50 V)
  • introducing the distance between the electrodes for the resistivity in metres (m),
  • memory of 990 measurements (10 banks of 99 cells each),
  • calibration of clamp used,
  • real time clock (RTC),
  • data transmission to the computer (USB, wireless),
  • indication of battery state.

Electric security:

  • type of insulation: double, according to EN 61010 – 1 and IEC 61557
  • measurement category: CAT IV 300 V acc. to EN 61010 – 1
  • protection class acc. to EN 60529: IP54

Rated operational conditions:

  • operation temperature: -10…+50°C
  • storage temperature: -20…+70°C
  • humidity: 20…80%

Other technical data:

  • LCD display: graphic, backlighted
  • interface: USB, wireless
  • number of measurements carried out of set of batteries: > 500
  • warranty: 24 months

Measurement of interference voltage

Range Resolution Accuracy
0…100 V 1 V ±(2% m.v + 3 digits)
  • singnalling overvoltage 24 V or 40 V rms
  • measurement for DC and AC 45…65 Hz,

Measurement of earth resistance (method 3- and 4-pole)
measurement range to IEC61557 – 5: 0,30 Ω…19,9 kΩ

Range Resolution Accuracy
0,00…19,99 Ω 0,01 Ω ±(2% m.v. + 2 digits)
20,0…199,9 Ω 0,1 Ω
200…1999 Ω 1 Ω
2,0k…9,99 kΩ 0,01 kΩ ±(5% m.v. + 4 digits)
10,0k…19,9 kΩ 0,1 kΩ
  • measurement current: under short circuit >200 mA,
  • voltage on open terminals: selectable <25 V AC or <50 V AC,
  • frequency of measurement current: 125 (for networks 50 Hz) or 150 Hz (for 60 Hz),

Measurement of continuity of equipotential bondings and protective conductors (Rcont)
measurement range to IEC61557 – 5: 0,24 Ω…19,9 kΩ

Range Resolution Accuracy
0,00…19,99 Ω 0,01 Ω ±(2% m.v. + 2 digits)
20,0…199,9 Ω 0,1 Ω
200…1999 Ω 1 Ω
2,0k…9,99 kΩ 0,01 kΩ ±(5% m.v. + 2 digits)
10,0k…19,9 kΩ 0,1 kΩ

 

  • voltage on open terminals: <24 Vrms but >4 Vrms,
  • measurement current: under short circuit >200 mA,
  • frequency of measurement current: 125 (for networks 50 Hz) or 150 Hz (for networks 60 Hz), possible choice of measurement frequency in menu,
  • auto-zero function measurement leads

Measurement of resistance of auxiliary electrodes RH and RS

Range Resolution Accuracy
0…999 Ω 1 Ω ±(5% (RS+RE+RH) + 8 digits)
1,00k…9,99 kΩ 0,01 kΩ
10,0k…19,9 kΩ 0,1 kΩ

Measurement of multiple earth resistance with using the clamp and auxiliary electrodes (3p + clamp)

Range Resolution Accuracy
0,00…19,99 Ω 0,01 Ω ±(8% m.v. + 3 cyfry)
20,0…199,9 Ω 0,1 Ω
200…1999 Ω 1 Ω
  • voltage on open terminals: selectable <25 V AC or <50 V AC,
  • measurement current: under short circuit > 200 mA,
  • frequency of measurement current: 125 (for networks 50 Hz) or 150 Hz (for 60 Hz),

Measurement of multiple earth resistance with using double clamps

Range Resolution Accuracy
0,00..19,99 Ω 0,01 Ω ±(10% m.v. + 3 digits)
20,0…149,9 Ω 0,1 Ω ±(20% m.v. + 3 digits)
  • frequency of measurement current 125 (for networks 50 Hz) or 150 Hz (for networks 60 Hz)

Measurement of ground resistivity
Measurement method: Wennera, ρ=2πLRE

Range Resolution Accuracy
0,0…199,9 Ωm 0,1 Ωm depending on measurement
accuracy RE with 4p method,
but not less than ±1 digit
200…1999 Ωm 1 Ωm
2,00k…19,99 kΩm 0,01 kΩm
20,0k…99,9 kΩm 0,1 kΩm
100k…999 kΩm 1 kΩm

L – distance between probes: 1…50 m

Data Sheet                                      

User Manual                                   

Declarations of conformity          

Firmware for MRU-120             

 

Related Products