I. Overview

The FZN25-12D/T630-20 indoor AC high-voltage vacuum load switch is an indoor device with three-phase AC 50Hz and rated voltage 12kV. It is suitable for use in power distribution stations and substations of industrial and mining enterprises as a protection and control device for electrical facilities. It is applicable to the switching load current, closed loop current, no-load transformer and cable charging current. Equipped with a grounding switch capable of closing short-circuit current. The operating mechanism can be manual or electric to facilitate the realization of the three remote control requirements of the power system.

2. Scope of application

The FZN25-12D indoor AC high-voltage vacuum load switch and the FZRN25-12D indoor AC high-voltage vacuum load switch-fuse combination appliance are control and protection devices for three-phase AC 50Hz, 12kV power distribution systems. They are widely used in industrial and mining enterprises and City building distribution stations and other places. Combination appliances are more reliable in protecting and using electrical equipment such as transformers than circuit breakers, and are particularly suitable for ring networks, dual-radiation power supply units and box-type substations.

3. Environmental conditions of use

Altitude ≤1000m

Ambient air temperature: upper limit +40℃, lower limit -25℃ (storage and transportation allowed at -30℃)

The daily average relative humidity of the air should not be greater than 95%, and the monthly average should not be greater than 90%.

Earthquake resistance: Earthquake intensity does not exceed level 8

The surrounding air should not be significantly contaminated by corrosive or flammable gases, water vapor, etc.

No frequent violent vibrations

Pollution level does not exceed Level II

4. Structural characteristics

◎This product uses a vacuum arc extinguishing chamber to extinguish arcs. It has stable and reliable performance, long electrical life, high number of opening and closing times, strong closing and opening capabilities, and easy operation and maintenance.

◎Integrate the switch body and operating mechanism into one, integrating isolating switch, load switch and grounding switch, with compact structure and small size.

◎The direct-acting isolation fracture and the vacuum arc extinguishing chamber are arranged in series, with high dynamic and thermal stable current parameters; the unique linkage according to the prescribed operating procedures enables the operation to be completed in one go.

◎Conical static contact, insulation cover and valve structure completely separate the busbar and load switch unit.

◎The vacuum load switch, grounding switch, valve, and switch cabinet door are strictly mechanically interlocked according to the "Five Preventions" to prevent misoperation and are safe and reliable.

◎The spring energy storage type operating mechanism can be opened and closed electrically or manually, making it easy to realize the three remote control requirements.

◎The power supply for opening and closing operation can be used for both AC and DC.

◎Manual opening and closing operations are usually on the right side of the load switch. Left operation can also be provided according to user needs, and the operation panel can also be lengthened.

5. Adoption of standards

GB3804-2004 《3.6KV~40.5KV AC high-voltage load switch》

GB16926-2009 《AC high-voltage load switch-fuse combination appliance》

IEC265-1 《High Voltage Load Switch Part 1: High Voltage Load Switch with Rated Voltage Above 1kV and Below 52kV》

IEC420 (1990) 《High-voltage AC load switch-fuse combination appliance》