Description
The MTD20KWR digital earth tester allows for the measurement of Earth Resistances and Soil Specific Resistivity, and also the spurious voltages caused by parasitic voltages present in the soil.
This equipment is suitable for fast and easy measurement of the grounding resistance in house and industrial buildings, hospital installations, lightning rods, antennas, substations, etc. Soil resistivity measurement allows for soil stratification in order to optimize the most complex grounding systems engineering.
Its state-of-the-art system of active and passive filters provides it with high immunity to electric interferences, making it possible to obtain reliable measurements even in the presence of spurious voltages, such as the ones that can be found in some urban areas and near primary substations.
A 1,470 Hz internal generator injects alternated current on the soil through an auxiliary rod. The voltage generated over the earth resistance is measured by the apparatus, and the resistance value is evaluated. The test current is automatically regulated.
It has abnormalities indications on the display which advises the operator when the generated current is not enough to carry out reliable measurements.
Because of its wide range of measurement (from 0.01 Ω up to 20 kΩ), this equipment allows for reliable testing in all kinds of soils, including those that offer very high resistivity.
This earth tester is supplied with a rechargeable internal battery. The smart charger is microprocessor-controlled, and can be powered from a 12 V car battery (or a similar one).
It has a sturdy, easy and safe to carry cabinet, with IP65 protection level (closed lid). It is suitable to work under adverse geographical and environmental conditions, with extreme temperatures in cold or tropical regions and in high mountain areas, showing a reliable performance in the field.
Technical specifications
Application
Measurement of grounding resistances (3 terminals), soil resistivity (4 terminals) and spurious voltages present in the soil.
Resistance measurement method
The equipment injects an electronically stabilised current in the soil, and measures, with high precision, the voltage developed in the soil by means of that current flowing through grounding diffusion resistances. Display shows the Resistance value.
Operation as a voltmeter
In the voltmeter function, the equipment operates as a AC conventional voltmeter, making it possible to check the presence and to measure voltages generated by parasitic currents.
Measurement ranges
Resistance: 0 - 20 kΩ.
Voltage: 0 - 200 V~.
Accuracy
Resistance and Resistivity measurements:
± 2% of the measured value ± 2 digits
Voltage measurement:
± 2% of the measured value ± 2 digits
Reading resolution
0.01 Ω in the resistance measurement;
0.1 V in the voltage measurement.
Output power and current
The output power is less than 0.5 W, and the output current is limited to less than 10 mA (max.).
Power supply
By means of an internal rechargeable NiMH battery, from a 12 V external battery.
Battery charger
A smart, microprocessor controlled, circuit adjusts the battery charge to the optimised parameters in order to ensure the maximum service life. It is supplied by means of an external AC adapter (provided with the equipment) or from a 12 V car battery.
Operation temperature
14 °F to 122 °F (-10 °C to 50 °C).
Storage temperature
-13 °F to 158 °F (-25 °C to 70 °C).
Humidity
95 % RH (without condensation).
Equipment weight
Approx. 3.3 lb (1.5 kg).
Dimension
8.70" x 7.44" x 3.90" (221 x 189 x 99 mm).