ERITECH® EST401 Ground Resistance Tester


ERITECH® EST401 Ground Resistance Tester

The handheld ERITECH® EST401 Ground Resistance Tester measures ground rod and small grid resistance in any season without the use of auxiliary ground rods. The tester can measure the resistance to ground, verify the quality of the grounding connections and bonds, and can measure the resistance and continuity of grounding loops around pads and buildings.

The ERITECH EST401 includes a current-measurement function. The probe’s high sensitivity enables measurement of current leakage flowing to ground or circulating in ground loops down to 1 mA and neutral currents to 30 Arms. A rugged Lexan® body and a double-walled Lexan shell (or equivalent polycarbonate) to encase the probe heads, offers strength and durability. Overall construction and mechanical design ratings meet or exceed IECSM standards. The product has been designed to meet IEC 1010.

Battery life information is given at power-up and auto-off and a large LCD makes viewing resistance and current-measurement easy. The ERITECH EST401 is ideal for measuring ground current and ground resistance at pole ground rods, service entrances, pad-mounted transformers, transmission towers, service panels, phone pedestals and central office locations. Extended distances between installations, such as high-tension towers, will not adversely affect the measurement results.


  • Offers fast and simple clamp-on operation
  • Requires no leads, auxiliary rods or spacing requirements
  • Provides a direct ground resistance reading of 0.1 to 1200 Ohms
  • Gives direct continuity and ground loop resistance readings
  • Offers direct ground leakage or phase current readings from 1 mA to 30 Arms
  • Accommodates 1000 MCM cables (1.25”/32 mm window) with its expansive jaw design
  • Has power management with auto-off
  • Resists breakage with durable head and body construction
  • Is designed to EN 61010-1, Cat III safety standards
  • Includes carrying case, user’s manual, battery and calibration loop


Measure ground rod and small grid resistance in any season without the use of auxiliary ground rods.

More Information

Resolution Accuracy
(% of Reading)
0.01 to 1200 Ohm
0.1 to 1.0 Ohm 0.01 Ohm ± (2.0% ± 0.02Ω)
1.0 to 50.0 Ohm 0.1 Ohm ± (1.5% ± 0.02Ω)
50.0 to 100 Ohm 0.5 Ohm ± (2.0% ± 0.05Ω)
100 to 200 Ohm 1 Ohm ± (3.0% ± 1.0Ω)
200 to 400 Ohm 5 Ohm ± (6.0% ± 5.0Ω)
400 to 600 Ohm 10 Ohm ± (10.0% ± 10.0Ω)
600 to 1200 Ohm 50 Ohm Not Rated
1 to 299mA 1mA ± (2.5% + 2μA)
Auto-Ranging 0.300 to 2.999A .001A ± (2.5% + 2μA)
1mA to 30.0Arms 3.00 to 29.99A .01A ± (2.5% + 20μA)
47 to 800Hz
Current Overload OL displayed
above 29.99Arms
Power Source 9V Alkaline battery
Battery life: 8 Hrs or
approx.1000 measurements
of 30 seconds


Ohms Range X
Arms Range X
Hold Function X
Self test X
Auto-Off X
Battery Life Indicator X
Noise Indicator X
Open Jaw Indicator X
Multi-Tone Beeper X

IEC is a registered service mark of Indepedent Electrical Contractors, Inc.
Lexan is a registered trademark of the General Electric Company.


ERITECH EST401 Ground Resistance Tester data sheet

ERITECH Clamp-on Ground Resistance Tester Model EST401 Instruction Manual