On October 11, 2023, Guangdong ETCR Electronic Technology CO.,Ltd. conducted grounding resistance measurement for towers at the sports center in Nancun Town, Panyu District, Guangzhou. The towers in focus were Tower No. 08 and Tower No. 09 of the 220KV Guangying A and B transmission lines.
During the measurement, a comparison was made using the digital meter four-wire method, clamp meter method, and the non-disassembly tower clamp four-claw method. The on-site measurement results are as follows:
1.Clamp Meter Method: This method does not require setting up ground stakes or connecting test lines. However, when testing a particular grounding down conductor, it is necessary to disconnect the other three grounding down conductors, which significantly increases the workload. The measured value was 4.5Ω, which differed from the four-wire method measurement. This discrepancy might be due to onsite interference.
2.Digital Meter Four-Wire Method: This method requires disconnecting the four grounding down conductors and setting up two grounding stakes, with four test lines connected. The workload is substantial, and there's a high risk of human error in operation. The measured value was 6.65Ω, which is considered accurate.
3.Tower Four-Clamp Method: There's no need to disconnect the grounding down conductors. Two grounding stakes are set up, and four test lines are connected. The four test clamps communicate with the main unit wirelessly, making the operation the most convenient and significantly reducing the workload for the operators. The measured value was 6.98Ω, which is considered accurate and closely matches the measurement from the four-wire method.
The measurement results confirm the accuracy of the ETCR3250 Non-Disassembly Tower Grounding Resistance Tester's data. It eliminates the need to disconnect the four grounding down conductors of the tower, allowing for rapid measurement of tower grounding resistance without altering the current grounding state of the tower. This method is safe and straightforward, significantly reducing labor intensity compared to traditional measurement techniques. It prevents operational errors that could change the grounding condition of the tower, providing information support for routine operation and maintenance, and emergency command work. This helps avoid lightning strike incidents caused by the grounding system of the transmission line not meeting the standards.
Key Features of the ETCR3250 Non-Disassembly Tower Grounding Resistance Tester:
1.Measures tower grounding resistance without disassembly, offering a quick, safe process that significantly reduces labor intensity.
2.Utilizes wireless communication between the current clamp and the main unit, preventing messy cable situations at the test site and saving time and effort.
3.Capable of measuring grounding resistance and soil resistivity using two, three, or four-wire methods, as well as measuring ground voltage and AC leakage current.
4.The current clamp can function independently as a clamp meter.
5.Grounding resistance range: 0.00Ω to 20.00kΩ.
6.Soil resistivity range: 0.00Ωm to 9000kΩm.
7.AC current range: AC 1.00mA to 500.0A.
8.Ground voltage range: AC 0.0V to 200.0V.
9.Clamp size: Φ68mm.
10.Data storage capability: Up to 2000 sets of data.
11.Alarm function: Allows for setting of alarm thresholds.
12.USB communication interface.
13.Bluetooth connectivity.
14.Rechargeable lithium battery.
15.Built-in printer.
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