The causes and solutions of the five common faults of high and low voltage electrical equipment, the analysis of the causes of electrical equipment, high and low voltage switchgear fault causes, mostly in the insulation, conductive and mechanical aspects.
1. Insulation fault:
Insulation level is to correctly deal with the relationship among various voltages (including operating voltage and overvoltage), various voltage limiting methods and insulation strength. Strive to make the product safe and economic, get good economic benefits. The main faults in insulation are flashover and breakdown of external insulation to ground, flashover and breakdown of internal insulation to ground, flashover and breakdown of interphase insulation, flashover and breakdown of lightning overvoltage, flashover, pollution flashover, breakdown and explosion of porcelain bushing and capacitor bushing, flashover of lifting rod, flashover, breakdown and explosion of CT, and fracture of porcelain insulator.
2. Current carrying fault:
The primary cause of current carrying fault caused by 72-12kv voltage level is poor contact of blocking plug of switch cabinet, which leads to contact burning.
3. Failure of refusing to operate and maloperation:
This kind of fault is the primary fault of high and low voltage switchgear, and its causes can be divided into two categories. One is caused by mechanical failure of operating organization and transmission system, which is characterized by tissue jam, deformation, displacement or damage of components, loose and jam of opening and closing iron core, loose and broken axle pin, tripping failure, etc. The other is due to the formation of electrical control and auxiliary circuit, such as poor contact of secondary wiring, loose terminals, wrong wiring, burning loss of opening and closing coil due to poor organization or poor transfer switch, ineffective switching of auxiliary switch, and operating power supply, closing contactor, micro switch on and off.
4. Breaking and closing fault:
This kind of fault is formed by the circuit breaker itself. For the less oil circuit breaker, the main performance is short circuit of fuel injection, burning of arc chamber, lack of breaking ability, explosion when closing, etc. As for vacuum circuit breaker, it is manifested as air leakage in arc extinguish chamber and bellows, vacuum drop, re ignition of capacitor bank, crack of ceramic tube, etc.
5. External force and other faults:
Including foreign body impact, natural disasters, short circuit of small animals and other unknown external forces and accidents.