Quotation for clamp type grounding resistance tester

ETCR2000Clamp type grounding resistance testerMeasurement of grounding resistance and loop resistance (range: 0.010 Ω~1000 Ω). When measuring a grounding system with a circuit, there is no need to disconnect the grounding lead or auxiliary electrodes. Simply clamp the clamp meter directly onto the grounding lead. At this time, the displayed value of the clamp meter is the comprehensive value of the grounding body resistance and the grounding lead resistance. This measurement method can quickly and safely obtain measurement results.

ETCR2000Clamp type grounding resistance testerIt can measure grounding faults that cannot be measured by traditional methods, can be applied in situations where traditional methods cannot measure, and is widely used for measuring grounding resistance of various equipment.

ETCR2000Clamp type grounding resistance testerfield application

When usingETCR2000 series clamp gaugeWhen testing with a clamp meter, for towers with double grounded down conductors, the connectivity diagram is shown in Figure 1. This method actually measures the on resistance of the circuit. When testing the conduction resistance of a circuit, the circuit includes the conduction resistance of the grounding grid circuit, the resistance of the grounding down conductor, and the conduction resistance of the tower itself. Therefore, the state of the tower itself will also affect the test results of the clamp meter. It should be noted that the contact resistance between the down conductor and the ground, as well as the anti-corrosion paint applied to the grounding down conductor of the tower itself, are also factors that affect the conductivity of the circuit.

Figure 1 Test Diagram for Conducting Resistance of Grounding Grid of Transmission Line Tower

If one of the two down conductors is disconnected or a single grounded down conductorFor the transmission line tower, the down conductor can form a circuit with the tower's grounding network through lightning protection wires and other tower grounding networks. At this time, the measured ground resistance is the grounding resistance. As shown in Figure 2.

Figure 2 Schematic diagram of grounding resistance test for transmission lines

Figure 3 Circuit diagram of equivalent grounding resistance of transmission line tower measured by clamp meter

Figure 3 shows the measurement of the grounding impedance of transmission line towers using a clamp meter, where R1+jXg is the grounding impedance of the tower to be measured. In the testing circuit of grounding resistance, it also includes the impedance of the lightning arrester (Z=R+jX) and the mutual impedance of the resistance between the towers (which is very small under normal grounding circuit conditions), as well as the equivalent resistance of the grounding resistance of other towers in parallel. According to the testing principle of a clamp meter, the resistance measured by the clamp meter is actually the sum of the four values mentioned above. So generally speaking, its test value is greater than the ZC-8 grounding shake meter value.

Use clamp gauges and grounding shake gauges to measure over 100 locations in Hunan ProvinceThe grounding resistance and grounding conduction resistance of transmission line towers involving different voltage levels were measured. Through extensive field tests, it was found that the grounding resistance measured by a clamp meter is generally larger than that measured by a ground shake meter, with an error generally less than 1 Ω. The conductivity measurement result of the clamp meter is 8-10 times that of the grounding shake meter. From the test data of two types of testing instruments, it can be seen that the conductivity measured by the clamp meter includes the conductivity of the grounding grid circuit, the resistance of the grounding down conductor, and the conductivity of the tower itself. The grounding shake meter only tests the conductivity resistance values of some down conductors and grounding grid circuits. Therefore, the test data of the clamp meter is much larger than that of the grounding shake meter, but it is more practical.

Through extensive on-site experiments, it has been found that the use of clamp gaugesWhen measuring the grounding conductivity of transmission line towers and grounding grids, as long as there is no significant deviation in the conductivity resistance value of the tower circuit for different down conductors and the measured conductivity resistance value is below 2 Ω, there is no rust or detachment of the tower grounding grid itself, only corrosion of the tower grounding grid. Figure 4 shows the on-site excavation of the 220 kV Zongbai Line 001 during the conduction resistance test at a certain power bureau in Hunan. It was found that the conduction resistance was significantly high, which also verified the effectiveness and practicality of using a clamp meter to measure the conduction of transmission line towers.

Figure 4 Excavation diagram of tower grounding device on site

compared with traditionalGrounding shaking meter,The clamp shaped meter is easy to carry, easy to operate, and has fast readings,Greatly shortened the time for testing the grounding resistance and conducting resistance of the tower, and improved work efficiency. By using a clamp meter for measurement, it is possible to determine whether there is rust or theft in the conductivity of the tower, laying the foundation for the development of online monitoring.

ETCR2000Clamp type grounding resistance testerTechnical Specifications