The disadvantages of the knife switch are the slow opening speed and the proximity of the operator to exposed live parts. Metal-enclosed safety disconnect switches are used for isolation of circuits in industrial power distribution. Sometimes spring-loaded auxiliary blades are fitted which momentarily carry the full current during opening, then quickly part to rapidly extinguish the arc.
The disadvantages of the knife switch are the slow opening speed and the proximity of the operator to exposed l:ive parts Metal-enclosed safety disconnect switches are used for isolation of circuits in industrial power dist!ribution Sometimes spring-loaded auxiliary blades are fitted which m.omentarily carry the full current during opening then quickly part to rapidly extinguish the arc