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d) test should comply with site safety regulations, Lei Yun should stop testing and
evacuate the test site when moving above the tower.
7.2.1 test methods
The method and principle of measuring the grounding impedance of transmission line
tower grounding device by three-pole method are basically the same as that of substation
grounding device, see figure 7. The maximum diagonal length of the tower grounding
device is D, when the grounding device of the tower under test has rays, the ray length L.
D taken Because there is usually no AC power supply and the ground grid is small, the
portable grounding impedance tester is generally used in the test site.
G— test tower grounding device; C one current pole; P one potential pole; maximum ray
length of L tower grounding device; distance between one current pole and tower
grounding device; distance between da— potential pole and tower grounding device.
Fig .7 Test diagram of grounding impedance of tower grounding device of transmission
line.
Before testing the grounding impedance of the tower, all the grounding lead lines of the
tower should be removed, that is, the electrical connection between the tower body and
the grounding device should be disconnected, and the grounding lead should be short
connected.
7.22 Wiring requirements and modalities
Wiring requirements refer to 61.2. The wiring
Summary of Contents for HZDW-DB
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