Ground Resistance Tester (Digital, 4-Point)
The Digital Ground Resistance Tester Model 4630Kit performs ground resistance and soil resistivity tests. This direct reading testers measures from 0 to 2000Ω, and is auto-ranging, so it automatically seeks outs the optimum measurement range. The Model 4630Kit is rugged, easy-to-use, and is ideal for maintenance crews performing numerous tests. It exceeds mechanical and safety specifications for shock, vibration, and drop tests called out in IEC standards. It is designed to reject high levels of interference, so it can be used under difficult conditions such as high stray currents that normally affect accuracy. The Model 4630Kit is powered by 9.6V, 3.5 Ah NiMH rechargeable batteries. A built-in recharge circuit, powered from a 120/230V 50/60Hz line, also provides for testing while recharging.
The large LCD (nearly 3/4" high characters) is easy-to-read, and also indicates low battery status, over-range, 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. Models 4620 and 4630 are fuse-protected up to 250VAC against accidental connection to live circuits. In the event of a system fault, they can with- stand 250VAC with spikes of 3000VAC or 1000VDC.
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.
The Model 4620 is powered by eight, C cell batteries.
The Model 4630 is powered by 9.6V, 3.5 Ah NiMH rechargeable batteries. A built-in recharge circuit, powered from a 120/230V 50/60Hz line, also provides for testing while recharging. Both models will perform over 2000 15-second tests between recharging (Model 4630) or battery replacement (Model 4620).
The Ground Resistance Tester Models 4620 and 4630 are rugged, easy-to-use instruments ideal for maintenance crews performing numerous tests. Both models exceed mechanical and safety specifications for shock, vibration and drop tests called out in IEC standards. They are designed to reject high levels of interference, so they can be used under difficult conditions such as high stray currents that normally affect accuracy.
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 the 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 (the outline of the part of equipment in contact with the earth) 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.