In the air-break circuit-breaker the contact separation and arc extinction takes place in air
at atmospheric pressure. As the contacts are opened, arc is drawn between them. The arc
core is a conducting 'path' of plasma. The surrounding medium contains ionized air. By
cooling the arc, the diameter of arc core is reduced. The arc is extinguished by
lengthening the arc, cooling the arc and splitting the arc. The arc resistance is increased to
such an extent that the system voltage cannot maintain the arc and the arc get
extinguished. This type of breaker is used for medium and low voltages.
There are two sets of contacts : Main contacts (1) and Arcing contacts (2). Main contacts
conduct the current in closed position of the breaker. They have low contact resistance
and are silver plated. The arcing contacts (2) are hard, heat resistance and are usually of
copper alloy. While opening the contacts, the main contacts dislodge first. The current is
shifted to the arcing contacts. The arcing contacts dislodge later and arc is drawn between
them (3). This arc is forced upwards by the electromagnetic forces and thermal action.
The arc ends travel along the arc Runners (Arcing horns). The arc moves upwards and is
split by arc splitter plates (arc chutes) (5) as shown by the arrow (4). The arc extinguished
by lengthening, cooling, splitting etc. In some breakers the arc is drawn in the direction of
the splitter by magnetic field.
Furthermore, air-break circuit-breaker have been developed with current limiting feature,
magnetic blow-up of arc, etc. Air break a.c. circuit breakers are widely used for industrial
switchgear, auxiliary switchgear in generation station. Air break principle employing
lengthening of arc, arc runners, magnetic blow-ups are used for d.c. circuit breaker up to
15 KV.
In the air-break circuit-breaker the contact separation and arc extinction takes place in airat atmospheric pressure. As the contacts are opened, arc is drawn between them. The arccore is a conducting 'path' of plasma. The surrounding medium contains ionized air. Bycooling the arc, the diameter of arc core is reduced. The arc is extinguished bylengthening the arc, cooling the arc and splitting the arc. The arc resistance is increased tosuch an extent that the system voltage cannot maintain the arc and the arc getextinguished. This type of breaker is used for medium and low voltages. There are two sets of contacts : Main contacts (1) and Arcing contacts (2). Main contactsconduct the current in closed position of the breaker. They have low contact resistanceand are silver plated. The arcing contacts (2) are hard, heat resistance and are usually ofcopper alloy. While opening the contacts, the main contacts dislodge first. The current isshifted to the arcing contacts. The arcing contacts dislodge later and arc is drawn betweenthem (3). This arc is forced upwards by the electromagnetic forces and thermal action.The arc ends travel along the arc Runners (Arcing horns). The arc moves upwards and issplit by arc splitter plates (arc chutes) (5) as shown by the arrow (4). The arc extinguishedby lengthening, cooling, splitting etc. In some breakers the arc is drawn in the direction ofthe splitter by magnetic field.นอกจากนี้ เบรกอากาศแบ่งได้ถูกพัฒนาขึ้น ด้วยคุณลักษณะจำกัดปัจจุบันblow-up แม่เหล็กโค้ง ฯลฯ แอร์แบ่งชื่อเบรคเกอร์ใช้สำหรับอุตสาหกรรมสวิตช์ สวิตช์ตัดเสริมในการสร้างสถานี อากาศแบ่งหลักการใช้ยาวของของส่วนโค้ง ส่วนโค้งรอบชิงชนะเลิศ blow-ups แม่เหล็กใช้สำหรับตัดวงจรดีซีถึง15 KV
การแปล กรุณารอสักครู่..