AMRU-10: earth resistance tester

AMRU-10: earth resistance tester

Earth resistance meter with 3-pole and 2-pole methods

The AMRU-10 measures earth resistance up to 9999 Ω by the technical 3-pole method per EN 61557-5 and by the 2-pole method, together with auxiliary electrode resistances and interference voltages up to 100 V, in an IP67 housing rated CAT IV 150 V.

Advantages

Two methods, one instrument
The technical three-pole method covers 0.53 to 9999 Ω at 50 V per EN 61557-5, and the two-pole method provides quick checks, both with resolution from 0.01 Ω and accuracy from ±(3 % of reading + 3 digits).

Trustworthy under disturbance
A measurement current above 20 mA at 125 or 150 Hz and a selectable 25 V or 50 V test voltage keep results accurate with disturbance voltages up to 24 V present, and interference voltages are measured up to 100 V.

Auxiliary electrodes verified
The resistances of the auxiliary electrodes RH and RS are measured up to 19.9 kΩ, confirming that the test setup itself is valid before the earth reading is taken.

Made for the field
An ergonomic, rugged IP67 housing, a large backlit segment display and simple, intuitive controls suit outdoor work in most environments.

Simple power, long life
Four AA alkaline batteries or NiMH accumulators with state indication and automatic power-off keep the meter ready; it weighs about 660 g with batteries.

Applications

  • Verification of earthing systems in electrical installations.
  • Earth electrodes of buildings, substations and lightning protection systems.
  • Assessment of earthing quality from the measured result.
  • Work by electrical installation contractors and maintenance technicians.

About the product

The AMRU-10 is rated CAT IV 150 V with double insulation per EN 61010-1 and IEC 61557 and meets the EMC standards EN 61326-1 and EN 61326-2-2; the set includes 30 m and 15 m test leads on reels, a 2.2 m lead, a crocodile clip, two 25 cm ground probes, AA batteries, carrying case, straps, handle and calibration certificate, with 80 cm probes and leads up to 200 m as options.

Technical specifications

Measuring methodsTechnical 3-pole per EN 61557-5; 2-pole
Earth resistance range0.53-9999 Ω (UN = 50 V); display from 0.01 Ω
Accuracy±(3 % m.v. + 3 digits) to 199.9 Ω; ±5 % / ±8 % above
Auxiliary electrodesRH and RS up to 19.9 kΩ; ±(5 % m.v. + 8 digits)
Interference voltage0-100 V; ±(10 % m.v. + 1 digit); RE valid up to 24 V
Measuring current> 20 mA (short circuit); 125 Hz or 150 Hz
Test voltageSelectable 25 V or 50 V
Power supply4 × AA alkaline batteries or NiMH accumulators
SafetyCAT IV 150 V; double insulation; IP67
Operating conditions-10 to +50 °C; humidity 20-90 %
Dimensions and weight221 × 102 × 62 mm; approx. 660 g with batteries

Frequently asked questions

Which measuring methods does it use?
The technical three-pole method (3p) per EN 61557-5 with auxiliary probes, and the two-pole method (2p) for quick resistance checks.

What range does it cover?
From 0.53 Ω to 9999 Ω at 50 V per EN 61557-5, with display resolution starting at 0.01 Ω.

Does it work with interference present?
Yes. It measures reliably with disturbance voltages up to 24 V present and measures interference voltages up to 100 V.

What is the measuring voltage?
Selectable between 25 V and 50 V, with a short-circuit measuring current above 20 mA at 125 or 150 Hz.

Is it suitable for outdoor work?
Yes. The IP67 housing, backlit display, CAT IV 150 V rating and roughly 660 g weight make it a true field instrument.

If you want to acquire Tellurometers with quality, you can also consult prices of Tellurometers.

If you have any doubts or need advice from our engineers, don't hesitate to contact us and we will be pleased to help you. You can also call us at (+34) 982 20 99 20.