FLBS an indoor high-voltage SF6 load switch, an switchgear with the rated voltage of 12kV/24kV, adopted with SF6 gas as an arc-extinguishing and insulation medium, including the three contactors for switching-on and switching-off and to-ground,and is characteristic in its small volume,its convenient installation and operation and its the great adaptability with surroundings.
FLBS of an indoor high-voltage SF6 load switch and FLBS of SF6 load switch plus fuse combination can function to protect and control the electric equipments for power supply and transformer substations especially being suitable for ring net cabinet, cable branch cabinet and distribution switching substation.
FLBS of an indoor high-voltage SF6 load switch and FLBS load switch plus fuse combination are complied with the standards of GB3804-1990, IEC60256-1,1997, GB16926, IEC60420 etc..
1. Altitude: 1000m;
2. Ambient temperature: -35 ~+40 ;
3. Relative humidity: daily average 90%; monthly average 95%;
4. Earthquake intensity: 8 degree;
5. Applicable occasions should be free from inflammable, explosives and severe vibration.
1. Stainless steel panel has good antisepsis and seal performance.
2. Light in weight and convenience for transit.
3. Maintenance Free.
4. With anti-explosive device.
5. The switch can be locked automatically when the press is 0.03 to 0.07MPa.
a) Air temperature
Maximum temperature: +40ºC; Minimum temperature:-35ºC
Monthly average humidity 95%; Daily average humidity 90% .
c) Altitude above sea level
Maximum installation altitude: 2500m
d) Ambient air not apparently polluted by corrosive and flammable gas, vapor etc.
e) No frequent violent shakea) Air temperature
Primary circuit loop of load break switch
Primary loop of FLBS indoor load break switch and its combination is sealed in a epikote casted insulate unit by APG technology, this insulate unit has features of good insulating property, dust and dirts proof, insulate unit contains upper and lower insulate covers, inside charged 0.4bars pressure SF6 gas, the partial siding of lower cover is very thin, it's a protective measure and will burst out in the malfunction, the over pressed gas is released to protect the equipment.
SF6 load break switch and its fuse combination has open,close and earth three working position.
FLBS load break switch adopts SF6 gas as the medium of arc extinction, when switch on and off, arc occurs and will spin under the magnetic field effect ion by the permanent magnet, cooled by the SF6 gas and extricated finally.
This indoor SF6 load break switch and its fuse combination works with spring type operating mechanisms A and K,AFL-12D load break switch equipped with the K spring operating mechanism is applied as the incoming control unit, while that equipped with A mechanism is applied as the outgoing protective unit and transformer unit.
1)K" Type Spring Operating Mechanism
Working principle of K type spring operating mechanism is spring press and release ( see fig 1. it's in off position)
Driven by the handle, upper crank arm 4 rotates and presses spring 2 to store energy, when the max energy reached continue rotate the crank arm, the energy storage spring starts to release energy and drive the upper trigger, enables the connecting bar to drive the crank arm, crank arm rotates and drives the moving contactor for earthing.
B)Switch on operation
Driven by the handle, lower crank arm 1 rotates, presses spring 2 to store energy, when the energy released, it drives the trigger 8,enables connecting bar to drive the crank arm, crank arm rotates and drives the moving contactor and load break switch turns on.
C)Switch off operation
Rotate the main shaft crank arm counterclockwise by the handle, release the energy storage spring and the load break switch turns off.
2)"A" Type Spring Mechanism
Working principle of A type mechanism is same as K type, in addition, it has fuse striker unbuckle function. For A type mechanism, electromagnetic unbuckle is also available on customers requirement.(see fig 2)
A)Switch on operation
Driven by the handle, lower crank arm 1 rotates to presse switch on spring 12 and switch off spring 8 at the same time, to provide sufficient energy required by switching off. when the lower crank arm 1 buckles the pin and drives trigger to move, it makes the lower roller wheel unbuckled, and release the switch on spring and load break switch turns on.
B)Switch off operation
Press the switch off button or push the unbuckle pin 2 by the fuse striker, release the spring and load switch turns off.
Earthing operation of A type mechanism is same as that of K type.
3)K type and A type operating mechanism can be operated manually or motorized on request.
***Notice: only when the load break turns off, can turning on and earthing operation be done.
FLBS indoor type medium voltage SF6 load break switch and its fuse combination has below interlocks:
A)When load break switch turns on, earthing operation can't be done
B)When earthing switch turns on, load break switch turns on/off operation can't be done
C)Interlock outlet of mishandling pretension is equipped