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Fluke 1621 GEO Earth Ground Tester

The 1621 is an easy-to-use earth ground tester that is your first line of defense in detecting reliable ground connections.

Fluke 1621 GEO Earth Ground Tester
  • Fluke 1621 GEO Earth Ground Tester
  • The Fluke 1621 is an easy-to-use earth ground tester. For ground resistance testing, the 1621 is the first line of defense in detecting reliable ground connections. The unit features basic ground testing methods including 3-pole Fall-of-Potential as well as 2-pole ground resistance tests. Its convenient size, rugged holster, and large, clear LCD display make it an ideal field earth ground tester, for most electrical grounding work environments. With a simple user interface and intuitive functionality, the Fluke 1621 is a handy grounding tool for electrical contractors, utility test engineers, and earth ground specialists.

    • Easily capture values with single-button operation
    • 3-pole Fall-of-Potential earth testing for basic measurements
    • 2-pole resistance measurements for added versatility
    • Ensure accurate measurements with automatic ‘noise’ voltage detection
    • Hazardous voltage warning offers increased user protection
    • Clearly read and record data with a large, backlit display
    • Rugged holster and design for tough work environments
    • Portable size allows for easy transportation
    • Instantly be alerted to measurements outside of your set limit, when you use the adjustable limit setting
    • 600 V Cat II
  • General Specifications
    Measuring functions 3-pole earth ground resistance, 2-pole ac resistance of a conductor, Interference voltage
    Intrinsic error Refers to the reference temperature range and is guaranteed for one year
    Measuring rate 2 measurements/second
    Battery1 One 9 volt alkaline (LR61)
    Battery condition LO-BAT is displayed if voltage drops below 6.5 V
    Voltages Between jacks H/C2 and E/C1 250 Veff maximum (effective voltage)
    Between jacks S/P2 and E/C1 250 Veff maximum
    Climatic class VDE/VDI 3540 RZ (conforming to KWG as per DIN 40040, 4/87)
    Temperature performance2 Working -10°C to +50°C (+14°F to +122°F)
    Operating 0°C to +35°C (+32°F to +95°F)
    Storage -20°C to +60°C (+68°F to +140°F)
    Reference +23°C ±2°C (+73°F ±4°F)
    Temperature coefficient ±0.1% of range per degree Kelvin
    Safety IEC/EN 61010-1, 600 V CAT II, pollution degree 2
    Dimensions 113 x 54 x 216 mm (4.5 x 2.1 x 8.5 in), including holster
    Weight 850 g (1.9 lb), including standard accessories, volume approximately 600 cm3
    Electrical Specifications
    Maximum deviations E1 Influence factor Position
    E1 Deviation influence 0%
    E2 Influence factor Supply voltage
    E2 Deviation influence 0%
    E3 Influence factor Temperature E3
    E3 Deviation influence 2.3%
    E4 Influence factor Serial interference voltage (20 V)
    E4 Deviation influence 0.6%
    E5 Influence factor Probe- and auxiliary probe resistance
    E5 Deviation influence 10%
    Test voltage 3.7 kV
    Protection type IP 40; IEC/EN 60529
    Electromagnetic compatibility Emission IEC/EN 61326 Class B
    Immunity IEC/EN 61326 Annex C
    RE Resistance measurement Measuring method Current-voltage measurement with improved cross-talk attenuation, no compensation of measuring lead resistance, with probe (3-pole) or without probe (2-pole), as per IEC/EN 61557–5
    Open circuit voltage 23 to 24 V AC
    Short circuit current > 50 mA AC
    Measuring frequency 128 Hz
    Maximum permissible overload 250 Veff
    Measuring time 8 seconds (average from when START is pressed)
    Limit input Tester retains set value even if instrument is turned off (assuming battery power supply is sufficient)
    Automatic changeover of resolution RH < 7 kΩ
    Resolution 0.01 Ω
    RH < 50 kΩ
    Resolution 0.1 Ω
    RH > 50 kΩ
    Resolution 1 Ω
    Interference voltage display DC + AC Vmax 30 Veff
    Common mode rejection > 80 dB at 50 Hz and 60 Hz
    Ri 680 kΩ
    Measuring uncertainty < 10% for pure AC and DC signals
    Measuring Range
    0.15 Ω to 20 Ω Resolution 0.01 Ω
    Display range 0 to 19.99 Ω
    200 Ω Resolution 0.1 Ω
    Display range 20 to 199.9 Ω
    2 kΩ Resolution 1 Ω
    Display range 200 to 1999 Ω
    Intrinsic Uncertainty ±(6% of measured value + 5D)
    Operating uncertainty IEC 615573 ±(18% of measured value + 5D)
    1. If the tester is not going to be used, or is being stored for a long period, remove the battery and store separately from the tester to avoid damage from battery leakage.
    2. The four temperature ranges for the tester exists to satisfy European Standards requirements; the instrument can be used over the full working temperature range by using the temperature coefficient to calculate accuracy at the ambient temperature of use.
    3. Covers all deviations caused by influence quantities E1–E5. If the deviation E4 caused by high probe or auxiliary probe resistance is higher than specified flashes. Measured values are outside of the specified operating uncertainty.
    • Models
      Model Name Description  
      Fluke 1621 Fluke 1621 GEO Earth Ground Tester


      • Users manual
      • Two measuring leads with alligator clips, 2 m (6 ft)
      • One battery, 9 V alkaline (LR61)
      • One protective holster, yellow
      • One CD-ROM
    • Cables & Hardware
      Model Name Description  
      Fluke GEO Fluke GEO Earth Ground Cable Reel 25 M Wire
      Fluke GEO Fluke GEO Earth Ground Cable Reel 50 M Wire
    • Cases & Holsters
      Model Name Description  
      Fluke-CXT280 Fluke CXT280 Extreme Case Fluke Store
    • Manuals
      1621 Users Manual Download
      1621 Users Manual Download
      1621 Users Manual Download
      1621 Users Manual Download
      1621 Addendum Download
      1621 Statement of Memory Volatility Download
    • Application Notes
      Checking ground electrode impedance for commercial, industrial and residential buildings Download
      How to use cable and pole earth ground testers Download
      Maintaining a solid ground Download
      Principles of earth grounding Download
    • Data Sheets
      Data Sheet for Fluke 1621 Download
    • Demos
      Earth Ground Resistance - Principles, Testing Methods and Applications Download
      Fluke 1621/1623/1625 Virtual Demo Download