summary
FZRN25-12/FZ (R) N25-12D indoor high-voltage vacuum load switch and FZRN25-12D/T200-31.5 indoor high-voltage vacuum load switch - fuse combination is the control and protection device of three-phase AC 50Hz, 12kV power distribution system. The product is oil-free, non-toxic, free of fire and explosion hazards, and is widely used in industrial and mining enterprises, urban building power distribution stations and other places. The latter is more reliable than the circuit breaker in protecting electrical equipment such as transformers, and is especially suitable for ring network, double auxiliary radio power supply unit and box-type substation.
FZRN25-12D/T630-20 indoor high-voltage vacuum load switch (hereinafter referred to as load switch) is an indoor device with three-phase AC 50Hz and rated voltage of 12kV. It is applicable to industrial and mining enterprise distribution stations, substations and other places, as the protection and control of electrical facilities, and is used for switching load current, closed-loop current, no-load transformer and cable charging current. It is a grounding switch with the ability to close short circuit current. Its operating mechanism can be manual and electric, which is convenient to realize the requirements of three remote control of power system.
FZRN25-12D/T200-31.5 indoor high-voltage vacuum load switch-fuse combination appliance (hereinafter referred to as combination appliance) is an indoor device with three-phase AC 5OHz and rated voltage of 12k, which is applicable to industrial and mining enterprise distribution substations, substations and other occasions for load control and short circuit protection. It also has a grounding switch with the ability to make short circuit current. Its operating mechanism can be manual and electric, which is convenient to realize the requirements of three remote control of power system.
Operating environmental conditions
◇ Ambient air temperature: upper limit+40 ℃, lower limit - 40 ℃; ◇ Altitude: not more than 1000m;
◇ Relative temperature: daily average is not more than 95%, and monthly average is not more than 90%; ◇ Seismic crack degree: less than 8 degrees;
◇ The surrounding air shall not be polluted by corrosive or combustible gases, water vapor and other harmful gases.
Specifications
FZN25-12/T630 vacuum load switch
FZN25-12D/630 vacuum load switch with grounding switch
FZN25-12R/T200 vacuum load switch - fuse combination
FZN25-12RD/T200 Vacuum load switch with grounding switch - fuse combination
Product structure and working principle
The FZN25-12 load switch adopts an integral frame assembly structure. The moving and stationary contacts in each phase circuit are closed in the vacuum tube to form a vacuum arc extinguishing chamber, which is installed on the integral insulation support with the relevant conductor; The upper end of the vacuum interrupter is connected with the upper and lower direct-acting isolating switch at the rear to form a conductive circuit through a conductive body; The dynamic and static contacts and conductors of the disconnector are also installed in the upper and lower integrated semi-closed insulation support. The entire organic insulation support is fastened on the metal frame. The spring energy storage operating mechanism is effectively combined with the characteristics of similar products in the same industry in the country, and installed on the side of the metal frame, greatly improving the operating life of the spring operating mechanism. If the lower conductor of the vacuum interrupter is installed with detachable fuse device, fuse and its buckle device, the load switch-fuse combination device is formed. The metal frame is equipped with grounding knife arm, spring operating mechanism and interlock; High-temperature resistant, flame-retardant and transparent plexiglass cover is installed between the moving and stationary contacts of the adjacent switch to effectively ensure personal safety; The grounding static contact is installed at the bottom of the load switch to form the load switch with grounding switch and the combined electrical appliance with grounding switch.
Vacuum chamber is adopted, with strong arc extinguishing ability, reliable and safe performance;
The vacuum load switch is integrated with the direct-acting disconnector and the operating mechanism, and the operation is simple. The disconnection and isolation can be completed at one time, and there are obvious visible fractures. The grounding switch can be equipped and interlocked with the switch. It is easy to operate, and can be operated manually and electrically. Each function has reliable interlocking, which is convenient for the interlocking design of the switch cabinet.
The fully insulated design is adopted. Each charged body is installed in the SMC insulation support frame. The conical insulation base and transparent glass cover are specially designed to isolate the incoming bus from the open phase and facilitate the design of armored switchgear.
Flexible installation and convenient maintenance; It can be installed in front or side, and the fuse replacement is more convenient.
Product structure and working principle
The load switch passes through the main shaft of the rotary switch. When the clockwise rotation angle is not more than 130 °, the disconnector is closed, and the mechanism spring stores energy. When the spring energy exceeds 130 °, the release of the spring energy will drive the drive part of the vacuum load switch to move, so that the moving contact of the vacuum arc extinguishing chamber will move upward and vertically to realize the closing of the switch. At this time, the opening spring stores energy. When the panel release device or release coil is pressed, The tripping half shaft in the mechanism acts, and the opening spring is released rapidly.
The grounding switch completes the energy storage and release action of the grounding switch spring by rotating the grounding spindle, drives the grounding knife to rotate, and realizes the closing and opening work of the grounding switch.
The work of the combined electrical appliance is to hit the release device of the load switch after any phase fuse is blown, drive the spring mechanism of the load switch with pre-stored energy to work, and realize the simultaneous opening of the three phases of the load switch. When the fuse is not replaced, the load switch cannot be closed.
Arc extinguishing principle:
The vacuum arc-extinguishing chamber equipped with FZN25-12D vacuum load switch and FZN25-12RD combined electrical appliance has a high vacuum degree. When the arc-extinguishing chamber moves and the static contact is powered off by the mechanism, a vacuum arc is generated between the contacts. Because the free electrode in the vacuum is small, it is not enough to maintain the arc. When the current naturally crosses zero, the arc will be extinguished, and the dielectric insulation strength between the contacts will recover quickly, reaching the purpose of breaking.
Action principle:
When closing, manually or electrically store the closing spring energy. When the spring passes through the center, it drives the cam to drive the switch spindle to rotate through the linkage mechanism to keep the switch in the closing state. When the main shaft of the switch is rotating, the first half of the switch is closed by the operating rod, and the static contact and the middle contact seat are connected, that is, the isolation break is closed, and there is no current at this time; The second half of the flashlight will not move, and the vacuum arc extinguishing chamber will be closed by the operating rod. The pre-breakdown arc in the arc extinguishing chamber will disappear with the closing of the moving and stationary contacts. When opening, manually or electrically disconnect the closing and holding (tripping half shaft) of the mechanism, and the switch spindle returns under the action of the opening spring. At this time, the operating rod separates the dynamic and static contacts of the vacuum arc-extinguishing chamber in the first half, and the current is cut off by the arc-extinguishing chamber, and the conductive resistance direction is kept at the closing position;
interlocking:
The interlocking between load switch, grounding switch and cabinet door adopts mandatory mechanical locking mode to ensure the "five prevention" function. Reliable mechanism interlocking is installed between load switch and grounding switch;
The microswitch constitutes a secondary control circuit. When the grounding switch is closed, the electric closing power of the load switch is disconnected, and the load switch cannot be closed;
The secondary control circuit composed of the microswitch linked by the tripping shaft, when the fuse causes the load switch to open, the fuse must be replaced before the load switch can be closed again. (Configured according to user requirements)
