Fluke 1625-2 Stakeless 2999 Count 7 Segment LCD 3&4-Pole GEO Earth Ground Tester
The Fluke 1625-2 (Part# 4325162) is an advanced GEO Earth Ground Tester capable of performing all four earth ground measurement methods in a single instrument: 3- and 4-pole fall-of-potential (with stakes), selective earth ground rod testing using one clamp and stakes, and fully stakeless testing using two current clamps — the latter eliminating the need to disconnect parallel grounds or locate suitable soil for auxiliary stakes, making it practical for indoor locations, power pylons, and paved sites. Automatic Frequency Control (AFC) identifies existing interference and selects a measurement frequency to minimize its effect, while an R* function calculates earth ground impedance at 55 Hz for a more accurate representation of real fault-to-earth conditions. The tester covers a resistance range of 0.02 Ω to 300 kΩ with an accuracy of ±(2% + 2 digits) for standard RE measurements and ±(7% + 2 digits) for selective and stakeless modes, backed by 120 dB noise rejection at 50/60 Hz. Rated IP56 for the case and IP40 for the battery door, it is built for demanding outdoor environments and is powered by six AA alkaline batteries delivering up to 6,000 measurements per set. Up to 1500 measurement records can be stored and downloaded via the USB port, and the large rotary switch with function keys is designed to be operated even with gloves on. The instrument ships with a user's manual, batteries, quick reference guide, and USB cable, with an optional full kit available that adds earth stakes, cable reels, and a carrying case
Key features:
- A unique earth ground tester that performs testing with and without stakes
- Tests 3- and 4-pole fall-of-potential, and 4-pole soil resistivity (with stakes)
- Performs selective earth ground rod testing (one clamp + stakes)
- Performs stakeless earth ground rod testing (two clamps)
- Features Automatic Frequency Control (AFC) to minimize the effect of interference
General
| Measuring functions |
Interference voltage/frequency, earthing resistance (3- and 4-pole),
selective (1 clamp + stakes), stakeless (2 clamps), resistance AC and DC
|
| Display |
4-digit (2999 count) 7-segment LCD |
| Memory |
Up to 1500 records via USB port |
| Data interface |
USB |
| Operation |
Central rotary switch and function keys (glove-operable) |
| Ingress protection |
IP56 (case) / IP40 (battery door) per EN 60529 |
| Safety |
Double/reinforced insulation · Max 50 V to earth per IEC 61010-1
· CAT II 300 V · Pollution degree 2
|
| Operating temperature |
-10 °C to +50 °C (14 °F to 122 °F) |
| Storage temperature |
-30 °C to +60 °C (-22 °F to 140 °F) |
| Temperature coefficient |
±0.1% of reading/°C (<18 °C or >28 °C) |
| Power |
6 × 1.5 V alkaline AA (IEC LR6) |
| Battery life |
~3,000 measurements (RE+RH ≤ 1 kΩ) / ~6,000 (RE+RH >10 kΩ) |
| Dimensions (W × H × D) |
250 × 133 × 187 mm (9.75 × 5.25 × 7.35 in) |
| Weight |
≤1.1 kg (2.43 lb) without accessories |
| Case material |
Polyester |
| Quality standard |
DIN ISO 9001 |
| Performance standard |
IEC 61557-5 |
Earthing resistance (RE) — 3- and 4-pole
| Measuring range |
0.020 Ω to 300 kΩ |
| Open circuit voltage |
20 / 48 V AC |
| Short circuit current |
250 mA AC |
| Measuring frequency |
94, 105, 111, 128 Hz (manual or AFC) · 55 Hz in R* mode |
| Noise rejection |
120 dB (at 16⅔, 50, 60, 400 Hz) |
| Accuracy |
±(2% of rdg + 2 digits) |
| Operating error |
±(5% of rdg + 5 digits) |
| Measuring time |
~8 s fixed frequency / 30 s max with AFC |
| Max probe resistance |
≤1 MΩ |
Resistance measurement AC (R~)
| Measuring range |
0.020 Ω to 300 kΩ |
| Measuring voltage |
20 V AC square pulse |
| Short circuit current |
>250 mA AC |
| Accuracy |
±(2% of rdg + 2 digits) |
| Operating error |
±(5% of rdg + 5 digits) |
| Measuring time |
~6 seconds |
| Max interference voltage |
24 V (above this, measurement blocked) |
Resistance measurement DC (R DC)
| Measuring range |
0.020 Ω to 300 kΩ |
| Measuring voltage |
20 V DC |
| Short circuit current |
250 mA DC |
| Accuracy |
±(2% of rdg + 2 digits) |
| Operating error |
±(5% of rdg + 5 digits) |
| Measuring time |
~4 s (includes polarity reversal) |
| Max inductivity |
2 Henry |
| Max interference voltage |
≤3 V AC or DC (above this, measurement blocked) |
Interference voltage measurement (UST)
| Measuring range |
1 V to 50 V |
| Display range |
0.0 V to 50 V |
| Resolution |
0.1 V |
| Frequency range |
DC / AC 45–400 Hz sine |
| Accuracy |
±(5% of rdg + 5 digits) |
| Internal resistance |
~1.5 MΩ |
| Max overload |
250 V rms |
Interference frequency measurement (F)
| Measuring range |
6.0 – 400 Hz |
| Display range |
16.0 – 299.9 Hz / to 999 Hz |
| Resolution |
0.1 Hz / 1 Hz |
| Accuracy |
±(1% of rdg + 2 digits) |
