Measures soil resistivity (4-Point). Measures ground resistance (2- and 3-Point) Fall-of-Potential method. This direct reading tester measures from 0 to 2000Ω, and is autoranging, so that it can automatically seek out the optimum measurement range.
Easy-to-use simply connect the leads, Press-to-Measure and read the results. The large LCD (nearly 3/4" high characters) is easy-to-read, and also indicates low battery status, overrange and test lead shorts and lead reversals. Three LED indicators on the front panel continuously warn the user of measurement problems to ensure accurate and reliable tests.
The AEMC 4620 Digital Ground Resistance Tester is fuse protected up to 250V AC against accidental connection to live circuits. In the event of a system fault, it can withstand 250V AC with spikes of 3000V AC or 1000V DC.
The heavy-duty field case is sealed against dust and water when closed. The meter itself is self-contained within an inner case providing additional environmental and insulation protection. The test button is also sealed against the elements.
This tester is powered by eight, C cell batteries and will perform over 2000 - 15 second tests between battery replacement. The AEMC 4620 Ground Resistance Tester is a rugged, easy-to-use instrument ideal for maintenance crews performing numerous tests. The AEMC 4620 exceeds mechanical and safety specifications for shock, vibration and drop tests called out in IEC standards. Designed to reject high levels of interference, so it can be used under difficult conditions such as high stray currents that normally affect accuracy.
Features
• Measures soil resistivity (4-Point) method
• Measures ground resistance (2- and 3-Point) Fall-of-Potential method
• Step voltage tests and touch potential measurements
• Auto-Ranging: automatically selects the optimum range
• Designed to reject high levels of noise interference
• Extremely simple to operate: connect - press - read
• LED on faceplate informs operator of high input noise, high auxiliary rod resistance and fault connections
• Battery powered
• Rugged, dustproof and rainproof field case
• Can also be used for continuity tests on bonding
• Color-coded terminals
Applications
• Three-Point measurements of resistance to ground of ground rods and grids. Three-Point measurements are generally used when the electrode or grid can be easily disconnected, if corrosion is suspected, or in circumstances where ground faults are unlikely to occur
• Four-Point tests or soil resistivity measurements. Locating areas of lowest soil resistivity is essential for achieving an economical grounding installation
• Touch potential measurements, an alternative to 3-Point tests in evaluating electrical safety. This test is recommended when the ground cannot be disconnected, where ground faults are highly likely to occur, or when the "footprint" of grounded equipment is comparable to the size of the ground to be tested.
• Two-Point tests for continuity tests on bonding or on pre-established grounds. This test is commonly performed in urban environments where proper auxiliary electrode placement may be obscured by confined real estate. Measurements are referenced against a good local ground conductor.