This FAQ has been written for NEAL (North East Africa and Levant) region. If you are looking for information for another region, please select the correct country from the top-left dropdown in the page and 'Navigate to Browse FAQs' in the Support menu.
SF circuit breakers use the puffer principle with SF6 gas.
This methods cools and extinguishes the electrical arc as it passes through zero current by puffing a gas compressed by a piston attached to the moving contact. The gas is channeled by an insulating nozzle towards the tubular arcing contacts that are used as an exhaust.
The operating sequence in a puffer-type breaking chamber with the moving part actuated by a control mechanism is as follows:
1- The circuit breaker is closed.
2- Following an opening order the main contacts separate (a) and the current is directed into the breaking circuit (b).
When the main contacts start to open the piston (c) slightly compresses the SF6 gas in the compression chamber (d)
3- An electrical arc appears on separation of the arcing contacts. The piston (c) continues its travel downwards.
A small quantity of the gas channeled by the insulating nozzle (e) is injected towards the arc.
For low current breaking, the arc is cooled by forced ventilation. However, for high currents the thermal expansion moves the hot gases towards cooler parts in the breaking unit.
The distance between arcing contacts becomes sufficient to allow breaking of the current when it passes through zero due to the dielectric properties of the SF6 gas
4 The moving parts finish their movement and injection of cold gas continues until the contacts are fully open.
he circuit breaker is open
This methods cools and extinguishes the electrical arc as it passes through zero current by puffing a gas compressed by a piston attached to the moving contact. The gas is channeled by an insulating nozzle towards the tubular arcing contacts that are used as an exhaust.
The operating sequence in a puffer-type breaking chamber with the moving part actuated by a control mechanism is as follows:
1- The circuit breaker is closed.
2- Following an opening order the main contacts separate (a) and the current is directed into the breaking circuit (b).
When the main contacts start to open the piston (c) slightly compresses the SF6 gas in the compression chamber (d)
3- An electrical arc appears on separation of the arcing contacts. The piston (c) continues its travel downwards.
A small quantity of the gas channeled by the insulating nozzle (e) is injected towards the arc.
For low current breaking, the arc is cooled by forced ventilation. However, for high currents the thermal expansion moves the hot gases towards cooler parts in the breaking unit.
The distance between arcing contacts becomes sufficient to allow breaking of the current when it passes through zero due to the dielectric properties of the SF6 gas
4 The moving parts finish their movement and injection of cold gas continues until the contacts are fully open.
he circuit breaker is open
Released for: Schneider Electric Egypt and North East Africa
This FAQ has been written for NEAL (North East Africa and Levant) region. If you are looking for information for another region, please select the correct country from the top-left dropdown in the page and 'Navigate to Browse FAQs' in the Support menu.
SF circuit breakers use the puffer principle with SF6 gas.
This methods cools and extinguishes the electrical arc as it passes through zero current by puffing a gas compressed by a piston attached to the moving contact. The gas is channeled by an insulating nozzle towards the tubular arcing contacts that are used as an exhaust.
The operating sequence in a puffer-type breaking chamber with the moving part actuated by a control mechanism is as follows:
1- The circuit breaker is closed.
2- Following an opening order the main contacts separate (a) and the current is directed into the breaking circuit (b).
When the main contacts start to open the piston (c) slightly compresses the SF6 gas in the compression chamber (d)
3- An electrical arc appears on separation of the arcing contacts. The piston (c) continues its travel downwards.
A small quantity of the gas channeled by the insulating nozzle (e) is injected towards the arc.
For low current breaking, the arc is cooled by forced ventilation. However, for high currents the thermal expansion moves the hot gases towards cooler parts in the breaking unit.
The distance between arcing contacts becomes sufficient to allow breaking of the current when it passes through zero due to the dielectric properties of the SF6 gas
4 The moving parts finish their movement and injection of cold gas continues until the contacts are fully open.
he circuit breaker is open
This methods cools and extinguishes the electrical arc as it passes through zero current by puffing a gas compressed by a piston attached to the moving contact. The gas is channeled by an insulating nozzle towards the tubular arcing contacts that are used as an exhaust.
The operating sequence in a puffer-type breaking chamber with the moving part actuated by a control mechanism is as follows:
1- The circuit breaker is closed.
2- Following an opening order the main contacts separate (a) and the current is directed into the breaking circuit (b).
When the main contacts start to open the piston (c) slightly compresses the SF6 gas in the compression chamber (d)
3- An electrical arc appears on separation of the arcing contacts. The piston (c) continues its travel downwards.
A small quantity of the gas channeled by the insulating nozzle (e) is injected towards the arc.
For low current breaking, the arc is cooled by forced ventilation. However, for high currents the thermal expansion moves the hot gases towards cooler parts in the breaking unit.
The distance between arcing contacts becomes sufficient to allow breaking of the current when it passes through zero due to the dielectric properties of the SF6 gas
4 The moving parts finish their movement and injection of cold gas continues until the contacts are fully open.
he circuit breaker is open
Released for: Schneider Electric Egypt and North East Africa
Need help?
Start here!
Find answers now. Search for a solution on your own, or connect with one of our experts.
Contact Support
Reach out to our customer care team to receive more information, technical support, assistance with complaints and more.
Where to buy?
Easily find the nearest Schneider Electric distributor in your location.
Search FAQs
Search topic-related frequently asked questions to find answers you need.
Contact Sales
Start your sales inquiry online and an expert will connect with you.
