【Daily Topic】【Electrical Edition 20160828】
Thread Content
Participation reward: 2 Wealth. Reward for the correct answer: 9 wealth. When the high-voltage and low-voltage systems in a substation share the same grounding system, in the high-voltage side of the substation that supplies power to the low-voltage system, if a grounding fault occurs in the high-voltage system, the substation and its equipment are considered safe as long as ( ) is satisfied. A. Heating pipes are used as grounding wires or protective wires. B. Thin-walled steel pipes or their outer coatings are used as grounding wires or protective wires. C. The grounding resistance of the exposed conductive parts in the substation shall not exceed 1 Ω. D. The total buried length of the high-voltage and low-voltage cables with metal sheaths in the substation exceeds 1 km. Correct answers: CD
When the high-voltage and low-voltage systems of a substation share a common grounding device, in the high-voltage side of the substation that supplies power to the low-voltage system, in the event of a grounding fault in the high-voltage system, the substation and its equipment are considered safe as long as condition (CD) is met. A. Heating pipes are used as grounding wires or protective wires. B. Thin-walled steel pipes or their outer coatings are used as grounding wires or protective wires. C. The grounding resistance of the exposed conductive parts in the substation shall not exceed 1 Ω. D. The total buried length of the high-voltage and low-voltage cables with metal sheaths in the substation exceeds 1 km
C. The grounding resistance of the exposed conductive parts in the substation shall not exceed 1 Ω. D. The total length of the high-voltage and low-voltage cables with metal sheaths that are buried in the substation exceeds 1 km
I’ll guess here; I think it’s C
C. The grounding resistance of the exposed conductive parts in the substation shall not exceed 1 Ω. D. The total length of the high-voltage and low-voltage cables with metal sheaths that are buried in the substation exceeds 1 km