FZN12A-12D/T630-20 type indoor AC high-voltage pneumatic type load break switch is three phases AC 50Hz, rated voltage of 12kV. It is used for CO load current, closed-loop current, no load transformer and cable charging current, making short circuit current. With earthing switch, the switch can withstand making short circuit current.
The operating mechanism can be operated by electrical or manual, which is easy to realize remote control.
Main application of indoor AC high-voltage pneumatic type load break switch
FZN12A-12D type indoor AC high-voltage pneumatic type load break switch is suitable to 12kV and below three-phase power distribution system, as control and protection for transformer, cable and overhead line. It is particularly suitable for terminal substation and box-type substation, and suitable for ring main unit, dual radiation power unit.
FZN12A-12D type pneumatic type load break switch can open and close load current and overload current. FZN12A-12D type pneumatic type load break switch-fuse composite apparatus can open and close load current, overload current and breaking circuit short circuit current.
Applying ambient conditions of indoor AC high-voltage pneumatic type load break switch
a.Ambient temperature: -25℃~+40℃
b.The height above sea level≤1000m.
c.Relative humidity: the average humidity of a day should be no more than 95%; the average humidity of a month should be no more than 90%.
d.Earthquake intensity: no more than 8 degree.
e.It should be installed in the place without dust, fire, chemical erosion, explosion, vapor and salt spray.
f.Pollution grade: II
Structural features of indoor AC high-voltage pneumatic type load break switch
1.It combines LBS, earthing switch and fuse on one frame. It is compact and with small volume, easy to installation.
2.Direct-acting isolating fracture, high dynamic and thermal stable current;it can be operated at one time due to unique linkage operating procedures.
3.With insulation cover of fixed contact, it isolates ring main unit on structure, saves isolation plate between phases and gaps, can preventing arc short circuit in switchgear
4.With unique shutter structure, when LBS opening, earthing switch closed and shutter closed, with good protective performance.
5.Load break switch, earthing switch and fuse are in accordance with “5 prevention” mechanical interlock, which can prevent misoperation and is safe and reliable.
6.Charged energy by spring operating mechanism, can closing and opening by electrical and by manual.
Main technical specification of indoor AC high-voltage pneumatic type load break switch
1min power frequency withstand voltage
between phases and to ground 42； between gaps 48.
Lightning impulse withstand voltage (peak)
between phases and to ground 75； between gaps 85
Rated short time withstand current (thermal stability current)
Rated short circuit duration
Rated short circuit making current
Rated active load breaking current
Rated closed loop breaking current
5% active load breaking current
Rated cable charging breaking current
Rated breaking no load transformer
Rated short circuit breaking current
Rated transfer current
Fuse striker output energy
Phase center distance
Air distance between phases
Inherent opening time of shunt release
Main circuit resistance