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Index: WMGBMMR620
Low resistance meter
Technical Specification
  • Description

    Measure motor winding resistance and other low resistances

    Possibility to measure objects of resistive and inductive nature with the use of versatile small resistance meter Sonel MMR-620.

    We present a professional small resistance meter MMR-620, which ensures high measuring accuracy - the measurement resolution is 1 µΩ. With the use of this device it is possible to perform measurements of objects of both resistive and inductive nature (e.g. testing of transformers or motors). The meter provides a high measuring current for individual subranges and various operating modes, adjusted to the type of measured object - quick measurement mode (3 sec) for testing objects of resistive nature, as well as extended measurement mode for testing objects of inductive nature.

    Product features

    MMR-620 microohmmeter enables accurate measurements of both connections resistance (welded, soldered, bolted) and winding resistance of electrical motors and power transformers.

    • Measurements of objects resistive in nature:
      • welded and soldered connections, equipotential bondings, earthing conductors,
      • contacts, welds of rails, conductors and cables,
      • measurement according to the four-lead method.
    • Measurements of objects inductive in nature:
      • motor windings,
      • low-resistance coils.

    Additional functions

    • Automatic or manual selection of measuring range (measurement of objects of an inductive nature).
    • Selection of measurement mode according to the type of measured object:
      • fast measurement (3 seconds) for measurement of objects of a resistive nature,
      • extended measurement for testing of objects of an inductive nature (accelerated mode, with slightly worse accuracy, available); with automatic discharging of the object after measurement.
    • Selection of measurement mode depending on application (including control of product series):
      • measurement in normal mode - triggered when the “START” button is pressed,
      • measurement in automatic mode - the instrument awaits connection of all four test leads to the object, after which it automatically start measurement in one or both directions and calculates the mean resistance value,
      • measurement in continuous mode - the meter repeats successive measurement cycles with breaks every 3 seconds (for objects of a resistive nature) or performs measurement continuously (for objects of an inductive nature)
    • Window mode:
      • makes possible to set an upper and lower limit within the measurement result should remain; sound signal triggered when the result is beyond set range,
      • capability of performing measurements even under disturbances of a value five times greater than the measured signal.
  • Technical Specification

    Resistance measurement

    Range Resolution Test current Accuracy
    0...999 μΩ 1 μΩ 10 A ±(0.25% m.v. + 2 digits)
    1.000...1.999 mΩ 0.001 mΩ 10 A ±(0.25% m.v. + 2 digits)
    2.00...19.99 mΩ 0.01 mΩ 10 A ±(0.25% m.v. + 2 digits)
    20.0...199.9 mΩ 0.1 mΩ 1 A ±(0.25% m.v. + 2 digits)
    200...999 mΩ 1 mΩ 0.1 A ±(0.25% m.v. + 2 digits)
    1.000...1.999 Ω 0.001 Ω 0.1 A ±(0.25% m.v. + 2 digits)
    2.00...19.99 Ω 0.01 Ω 10 mA ±(0.25% m.v. + 2 digits)
    20.0...199.9 Ω 0.1 Ω 1 mA ±(0.25% m.v. + 2 digits)
    200...1999 Ω 1 Ω 0.1 mA ±(0.25% m.v. + 2 digits)

    m.v. - measured value

  • Files