The AMRU-200 GPS measures earth resistance by the 2, 3 or 4-pole technical method, by the pulse method with three pulse slopes (4/10 μs, 8/20 μs and 10/350 μs) and with a double clamp with no auxiliary electrodes. It also measures soil resistivity by Wenner's method, current with clamps and the continuity of compensating and protective connections, and stores the satellite position and the time of every reading in its memory.
Advantages
Every method in a single meter
Earth resistance by the 2, 3 or 4-pole method, pulse method, double clamp and soil resistivity, without swapping instruments at each point.
Multiple earths without disconnecting the installation
With auxiliary electrodes and clamps, or with a double clamp when electrodes cannot be placed, it measures each electrode of an earthing network without disconnecting it from the rest.
Satellite positioning and real-time clock
The built-in GPS receiver stores the coordinates of each measurement together with the time stamp from the real-time clock (RTC), making it easier to identify each electrode and carry that data over into inspection reports without writing it down by hand.
Measurement in the presence of disturbance voltage
It measures with disturbance voltage present on the network at 16 2/3 Hz, 50 Hz, 60 Hz or 400 Hz, with automatic or manual frequency selection.
Memory and transfer to a PC
990 measurements in 10 banks of 99 cells, transferred to the computer over a USB cable; an optional program builds documentation from that data.
Applications
- Checking earth electrodes and earthing networks in substations and industrial installations.
- Soil resistivity studies for earthing system design.
- Measuring multiple earths without disconnecting the installation, with clamps or a double clamp.
- Continuity of compensating and protective connections with a self-neutralising function.
About the product
The meter also measures the resistance of the RH and RS auxiliary electrodes, read independently on the right-hand side of the display, and current with clamps -including leakage current-. The distance between electrodes for resistivity is entered in metres or feet, and the clamps used are calibrated from the meter itself. It runs on a Ni-MH 4.8 V 4.2 Ah battery set, good for more than 300 measurements per charge, and meets CAT III 600 V measurement category and IP54 protection.
Technical specifications
| Measurement methods | 2, 3 and 4-pole; pulse; double clamp; resistivity (Wenner) |
| Earth resistance (3/4-pole) | 0.00 Ω to 19.9 kΩ, according to IEC 61557-5 |
| Soil resistivity | 0.1 Ω·m to 999 kΩ·m |
| Continuity | 0.24 Ω to 19.9 kΩ, according to IEC 61557-5, current >200 mA |
| Alternating current (with clamps) | 0.1 mA to 300 A |
| Memory | 990 measurements (10 banks of 99 cells) |
| Positioning and clock | Built-in GPS and real-time clock (RTC) |
| Power supply | Ni-MH 4.8 V 4.2 Ah battery; more than 300 measurements |
| Safety | CAT III 600 V; IP54 |
| Environmental conditions | -10…+50 °C operating; -20…+70 °C storage |
Frequently asked questions
Which earth-resistance methods does it support?
The 2, 3 or 4-pole technical method, the pulse method with three pulse slopes and the double-clamp method, plus soil resistivity by Wenner's method.
What are the GPS coordinates for?
Every measurement is stored with its position and the time from the real-time clock, which makes it easier to identify each electrode on installations with many earthing points and complete inspection reports without writing the data down by hand. The GPS gives the position as latitude and longitude (WGS84). If the site drawings use UTM, ETRS89 or the older ED50, the coordinate converter translates it from one system to the other right in the browser.
Can it measure multiple earths without disconnecting them?
Yes, with auxiliary electrodes and clamps, or with a double clamp when auxiliary electrodes cannot be placed.
How many measurements does the memory hold?
990, held in 10 banks of 99 cells, transferable to a computer over USB.
