The lightning protection installation plays an extremely important role. It protects a house or other building against lightning strikes and, consequently, fire, but also safely discharges energy to the ground in the shortest possible way. To increase work efficiency, but also to ensure proper operation of the entire installation, a grounding resistance meter should be used.
Check the earth resistance meters at the Onninen wholesaler
What is the measurement of earth resistance?
Properly performed grounding should have the lowest possible resistance value, but also the lowest possible resistance variation over a given period of time. You need to know that measuring ground resistance involves placing the current probe at an appropriate distance from the ground. Voltage probes should be placed halfway up the distance. Please remember that both the earth electrode and the probes must be in a straight line. During the measurement, the voltage drop on the ground is measured. The earthing resistance is measured to check whether the electrical installation works properly and meets the requirements for proper protection against electric shock. Thanks to the resistance, you can determine the value of the touch voltage.
This may occur between conductive parts located on the protective conductor. Unless special guidelines are specified, it is recommended that the resistance does not exceed 10 Ohm. Resistance measurement is easiest done with an ohmmeter, which determines electrical resistance. Its unit is Ohm. This device is used to determine not only the resistance of resistors, but also measures electronic components and resistors. Resistance should be determined using a technical method that takes into account the parallel connection of the voltmeter to the voltage source, as well as the voltage drop and current.
What value should the earth resistance have?
Testing the earth electrode is important and involves discharging any electrical discharges to the ground. The resistance measurement value should be as low as possible. It is best not to exceed 10 Ohms. At the same time, we can only talk about fully correct operation if the variability over time is also as small as possible. In single-family houses, this value should also not exceed 10 Ohm. Additionally, in new houses it is recommended to use additional RCD switches and surge protection. Remember that the permissible error when measuring earth resistance cannot be more than 30%, and the measurement voltage at the meter terminals depends on the value of the measured insulation resistance RI. The value cannot be less than the nominal voltage of the earth resistance meter , provided that the measurement current does not exceed 1 mA.
Earth resistance meters at the Onninen wholesaler
When looking for high-class devices at the Onninen electrical wholesaler , you can choose the Sonel MRU-21 grounding resistance meter . It is an extremely effective device that has a calibration certificate. It also has built-in memory, which allows you to quickly and easily compare results. It also has an automatic discharge function, so this earth resistance meter is completely safe and easy to use.
It is also worth using the Sonel MRU-200 grounding resistance meter . It uses all measurement methods, which really distinguishes it from the competition, so you can use both the technical method and the method using additional clamps. It also uses the impulse method. It has a soil resistivity measurement function. Despite a number of functions, it is extremely accurate. Automatically calculates soil resistivity. The manufacturer used a clamp calibration function as well as measurement of interference voltages. This device is perfect for difficult working conditions. There is no need to disconnect the control connectors.
Also noteworthy is the Fluke 1630-2 FC ground resistance meter . It is extremely precise in measurements, which allows you to precisely determine the value of grounding resistance. For even greater convenience of work, it is equipped with an easy-to-use interface. The manufacturer also used the automatic measurement range detection function. Before each measurement, the counter resets to zero. Thanks to this, you don't have to worry about mistakes. The casing is resistant to mechanical damage.