1 Purpose and Usage
The product divides into Type I and Type II. Product of Model LW3-12I has the function of manual -store-energy open and close circuit, manual close circuit and over current (or short circuit ) free trip open circuit. It is mainly used in branch circuit of 10kV and can completely replace existing on-pole oil circuit breakers.
Product of Model LW3-12Ⅱ, equipped with (AC/DC 220V) motor-store-energy spring-trigger device, has the function of motor-dive store-energy, motor-dive close circuit, motor-dive open circuit, manual close circuit, manual open circuit and over current (or short circuit ) free trip open circuit ( carried out by build-in or external current transformer). It is mainly used as circuit breaker or main switch in side outlets of medium-sized or pint-sized transformer stations. It is also suitable for controlling and protecting single high voltage electric apparatus of 10kV.

2 　 Features
Outdoors high SF6 voltage circuit breakers of Model LW3-12Ⅰ and LW3-12Ⅱare new types that using SF6 as arc extincting and insulating medium. The arc-extinquish chamber adopts Self-energy Revolve Arc Theory, making the circuit breaker and the control device an integer. Compared with other outdoors circuit breakers of 12kV class, it is distinct excellence of brief structure, reliable arc-extinction and insulation property, low control power, high nominal parameter, long service life, long repair period, etc. It is the ideal product to replace on-pole oil circuit breakers.