40.5kv 33kv 36kv Sf6 Circuit

Item:40.5kv 33kv 36kv Sf6 Circuit Breaker

The 40.5kV, 33kV, and 36kV SF6 Circuit Breaker is designed for three-phase AC 50Hz, 35kV power transmission and distribution systems. It serves as a control and protection device and can also be used as a tie circuit breaker or for switching capacitor banks.

Characteristics of SF6 Gas:

Density: SF6 gas is 5.135 times heavier than air.

Boiling Point: -60°C at atmospheric pressure.

Chemical Stability: Below 150°C, SF6 remains chemically inert and does not react with metals, plastics, or other materials in the circuit breaker.

Arc Decomposition: When decomposed under the high temperature of an arc, SF6 quickly re-synthesizes after arc extinction, with no carbon content and no risk of oxidation due to air contact.

Dielectric Strength:

At 1 atm, SF6 has 2-3 times the dielectric strength of air.

At 3 atm, its dielectric strength can meet or exceed that of traditional insulating oils.

Interrupting Performance: SF6 has exceptional interrupting capacity, 100 times that of air in a basic open chamber. As the arc current nears zero, a high-temperature core in the arc column—encased by a non-conductive layer—helps the dielectric strength of the arc gap recover rapidly after the current passes zero.

Model Description

Main Technical Parameters

Structure And Mounting Dimensions

Working Environment：

Item:40.5kv 33kv 36kv Sf6 Circuit Breaker

Installation and Operating Conditions

Installation Method: Side-mounted, middle-mounted

Ambient Air Temperature:

Maximum: +40°C

Minimum: -30°C

Altitude: ≤2000m (for altitudes above 2000m, increase the rated insulation level accordingly)

Wind Pressure: ≤700 Pa (equivalent to wind speed of 34 m/s)

Seismic Intensity: Up to 8 degrees

Contamination Level: Class I

Maximum Daily Temperature Variation: ≤25°C

Possible causes of electrical circuit failure

Item:40.5kv 33kv 36kv Sf6 Circuit Breaker

Insufficient Insulation: Deterioration or contamination of insulation material can lead to breakdowns.

Moisture Ingress: Entry of moisture into the SF6 gas chamber can reduce the dielectric strength and lead to faults.

Gas Leakage: Leakage of SF6 gas can decrease insulation and interrupting capabilities.

Mechanical Failures: Worn-out or damaged moving parts, such as mechanisms in the circuit breaker, can impair operation.

Contact Erosion: Frequent switching can cause erosion of contact points, reducing the circuit breaker's effectiveness.

Overloading: Excessive current flow beyond the rated capacity can lead to overheating and damage. 

Product Real Shot

FAQ

Q1: What is the main function of the SF6 circuit breaker?
A1: It is used for controlling and protecting power transmission and distribution systems, and can also be used as a tie circuit breaker or for switching capacitor banks.

Q2: What gas is used in the circuit breaker and why?
A2: SF6 gas is used for its excellent arc-extinguishing and insulation properties. It has high dielectric strength and does not react with other materials commonly used in circuit breakers.

Q3: How does SF6 compare to air in terms of insulation?
A3: SF6 has a dielectric strength 2-3 times higher than air at 1 atm and can exceed that of insulating oil at higher pressures.

Q4: What are the environmental conditions for proper operation?
A4: The ambient temperature should be between +40°C and -30°C, the altitude should be ≤2000m (higher altitude requires increased insulation), wind pressure should not exceed 700Pa, and the contamination level should be Class I.