Amprobe GP-2
Ground Resistance & Resistively Tester
See: Amprobe Ground Resistance Testers

  • Measures Earth ground resistance - 3 point (fall of potential) or 2 point tests
  • Automatically calculates resistivity - 4 point test
  • Automatic voltage measurement prevents false measurements
  • Automatically applies three testing frequencies for the most accurate readings
  • Test leads, auxiliary electrodes and software are included for complete instrument
  • Auto ranging
  • 999 internal memory locations to store measurements
  • RS-232 download to a personal computer

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Product Information
Datasheet 318 KB
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Resistance Measurement

Range (Ω) Resolution (Ω) Accuracy
0.01 ÷ 19.99 0.01 ±2% reading ± 3 Digits
20.0 ÷199.9 0.1
200 ÷ 1999 1

Resistively Measurement ρ

Range (**) Resolution Accuracy (*)
0.6 - 125.6Ωm 0.1Ωm ±2% reading ± 3 Digits
0.125 - 1.256kΩm 0.001Ωm
1.25 - 19.99kΩm 0.01Ωm
20.0 - 199.9kΩm 0.1Ωm
Testing Frequency 125Hz/75Hz/41.66Hz
Testing Current 10mA
Open Terminal Measuring Voltage 25Vrms
Waveform of Measuring Voltage Sine Wave
Amperometric circuit The measurement is taken with the stated accuracy if the interfering Voltage is ≤3V, while for interfering voltages between 3 and 30V inclusive, the accuracy decreases progressively; with interfering voltage of about 30V the instrument does not perform the test.
Voltmetric Circuit The measurement is taken if the interfering voltage is ≤3V; in case of higher voltages the instrument does not perform the test.
Interfering Voltage Measurement Range (V) (**) Resolution (V) Accuracy
500 1 ±(2% reading ± 2 Digits)
Additional Notes (*)=If Rρ > 100RE and/or RC > 100RE, Rρ > 50kΩ and/or RC >  50kΩ, if the instrument carries out the test the accuracy of the instrument is ±(10% Reading)
Rρ =  Resistance of the voltage circuit
RC= Resistance of the current circuit
RE= Earth resistance
ρ=  2PiDRE = Calculated Resistivity

(**)= Automatic Selection of range

Ground Leakage/Current

Auto Range Yes
Hz 50/60 Hz
True RMS Yes
Crest Factor <3.0
Accuracy of Resistance Calibration Plate ±0.5%
Data Logging Capacity 116 records
Data Logging Interval 1 to 255 seconds
Safety Standards
Complies with EN61010, EN 61557-1, EN61557-5
Insulation Class 2, Double Insulation
Pollution 2
Maximum Altitude 2000m
Surge voltage category CAT III 250V (phase to earth)
Power Specifications
Battery Type 1.5V size AA (6)
Low Battery Indication appears on display when power voltage is low
Battery Life About 300 Measurements
Fusible Link F 100 mA (not accessible to the operator)
Auto Power off Instrument will shut down after 2 minutes of inactivity after last selection of a function or PC command
General Specifications
Reference Temperature 73 ± 41ºF (23ºC ± 5ºC)
Operating Temperature 14 ± 122ºF (-10ºC ÷ 50ºC)
Reference Humidity <80%
Storage Temperature -4F ± 140ºF (-20ºC ÷ 60ºC)
Storage Humidity <70%
Dimension (LxWxH)

8.74" x 6.38" x 2.25" inches

Weight 2.2lbs/1000g
Ordering Information
Model Description Buy Online List Price
GP2  Amprobe GP-2 Ground Resistance & Resistivity Tester Discontinued
See: Amprobe Ground Resistance Testers
Included Accessories
  • 1 -  Carrying Case Kit (Earth Rod x4; Banana crocodile cables x4)
  • 1 - GP-2CC - Carrying Case
  • 1 - Optical Serial Cable


Optional Accessories
MFR ID: 2733461
Amprobe RS-USB USB to RS-232 Adapter Buy Now Sale $55.96
(Reg. $69.95)