In power system operations and maintenance, the stable operation of SF6 load switches and indoor high-voltage grounding switches directly impacts power supply safety and maintenance reliability. Prolonged use of these devices can lead to faults, and timely troubleshooting prevents fault escalation and minimizes downtime losses.
I. Common Failures and Solutions for SF6 Load Switches
1. Difficulty Closing: Primarily caused by stuck operating mechanisms, deformed linkages, or oxidized contacts
Solution: After de-energizing, lubricate the operating mechanism to release jams; straighten or replace deformed linkages; polish oxidized contacts to ensure smooth, tight contact.
2. Incomplete Opening: Prone to causing short circuits or overloads. Causes include insufficient spring force, mechanism corrosion, or line jamming.
Solution: Inspect and replace springs with inadequate force; remove rust and lubricate corroded mechanisms; clear line obstructions to ensure full opening travel.
3. Difficult arc extinction/arc chamber malfunction: Core causes include SF6 gas leakage (insufficient arc-quenching medium), failed arc chamber seals, or abnormal contact gaps.
Solutions: Locate leaks using an SF6 gas leak detector, repair seals, and replenish qualified SF6 gas; replace damaged arc chambers; precisely adjust contact gaps per manual specifications.
II. Common Faults and Solutions for Indoor High-Voltage Earthing Switches
1. Poor Earthing: Threatens maintenance safety. In indoor environments, causes include dust accumulation and oxidation on contacts, loose earthing wires, or corroded connectors.
Solutions: Clean dust from contacts and polish oxidation layers to ensure proper contact; tighten earthing wire bolts; replace severely corroded earthing wires and connectors to ensure earthing resistance meets standards.
2.Unreliable Closing: Indoor environments may cause transmission mechanism jamming due to dust accumulation or operating handle malfunctions, leading to grounding protection failure.
Solutions: Disassemble and clean the transmission mechanism, applying specialized grease; repair or replace damaged operating handle components to ensure reliable locking after closing.
3.Misoperation: Prone to causing short circuits, caused by interlock device failure.
Solutions: Inspect, repair, or replace failed interlock components; calibrate parameters to ensure closing is only possible during equipment shutdown for maintenance.
III.Summary
The core of fault prevention lies in regular inspection and maintenance. For SF6 load switches, focus on monitoring SF6 gas pressure and sealing integrity. For indoor high-voltage grounding switches, prioritize indoor dust and moisture prevention, and regularly clean transmission components.
