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.

3-pole Fall-of-Potential earth testing for basic measurements 2-pole resistance measurements for added versatility Easily capture values with single-button operation 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

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 61557[1]	± (18 % of measured value + 5D)
Notes:	[1] 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.