12KV Permanent Magnet Latching Vacuum Contactor

The G3NA series high-voltage permanent magnet latching vacuum contactor (hereinafter referred to as the "contactor") is suitable for power network systems with AC frequency of 50-60Hz, a rated voltage of 12KV in the main circuit, and rated currents ranging from 400A to 1250A. It is designed for remote connection and disconnection, as well as frequent starting and control of AC motors, transformers, capacitor banks, and other applications.

Environmental Conditions for Use:

Ambient temperature: -25°C to +40°C.
Installation altitude: Not exceeding 2000m.
Relative humidity of the air: The maximum relative humidity in the wettest month is 90%, and the average minimum temperature of the month is +25°C. 
Consideration should be given to frost formation on the product surface due to temperature changes.

Structure and Operating Principles

Structure:
This series of switches is composed of an insulated separating frame, a transmission lever, an electromagnetic system, auxiliary switches, and a vacuum contactor tube. The structure features a high-voltage circuit and a low-voltage control with a vertically separated design. It is aesthetically pleasing, safe, reliable, and easy to install and maintain.

Operating Principles:

Permanent Magnet Type:
This series of vacuum contactors adopts the most advanced bistable permanent magnet operating mechanism as the main driving component. With few operating elements and simple control, it has a low closing and opening current, ensuring safety and reliability. In the closed or open state, the control circuit does not need a long-term live power supply, achieving energy-saving and reliable effects.

Vacuum Contactor Tube (Vacuum Arc Extinguishing Chamber):
This component is the heart of the contactor, consisting of upper and lower cover plates, a glass or ceramic outer shell, a corrugated tube, and moving and fixed conductive rods. It forms a sealed chamber and is evacuated to high vacuum. The moving and fixed conductive rods are welded with a pair of wear-resistant current-interrupting materials to create a good breaking contact. The corrugated tube serves to isolate the atmosphere and allows the contact to move up and down.

Due to the vacuum chamber, the vacuum tube cannot withstand external impacts, and the corrugated tube cannot undergo rotational distortion; otherwise, it may leak air and become damaged.

Model	G3NA-400/12	G3NA-630/12	G3NA-800/12	G3NA-1000/12	G3NA-1250/12
Rated Current:	400A	630A	800A	1000A	1250A
Rated Voltage of Main Circuit (KV)	12	12	12	12	12
Rated Current of Main Circuit (A)	400	630	800	1000	1250
Rated Short-Circuit Breaking Current (KA)	16	16	16	16	16
Rated Short-Circuit Making Current (KA)	31.5	31.5	31.5	31.5	31.5
Rated Peak Withstand Current (KA)	20	20	20	20	20
Mechanical Life (ten thousand times)	25	25	25	25	25
Main Circuit Power Frequency Withstand Voltage (Isolation) (KV)	42	42	42	42	42
Phase-Phase, Phase-Ground Power Frequency Withstand Voltage (KV)	42	42	42	42	42
Lightning Impulse Withstand Voltage (KV)	75	75	75	75	75
Control Circuit Power Frequency Withstand Voltage (KV)	2.5	2.5	2.5	2.5	2.5
Terminal Pressure (N)	>800	>800	>800	>800	>1000
Contact Opening Distance (mm)	8±1	8±1	8±1	8±1	8±1
Overtravel (mm)	2±0.5	2±0.5	2±0.5	2±0.5	2±0.5
Main Circuit Contact Resistance (μΩ)	≦150	≦100	≦100	≦100	≦100
Weight (kg)	30	30	35	35	35

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The primary difference between permanent magnetic latching type and electrical holding type vacuum contactors lies in the mechanism used for maintaining the contactor in the closed position.

Permanent Magnetic Latching Type Vacuum Contactor:

Operating Mechanism:Utilizes a permanent magnet as the main driving component to keep the contacts closed.
Advantages:Fewer operating elements, simple control, low closing and opening currents, and energy-saving as the control circuit does not require a continuous power supply in the closed or open state.
Application:Suitable for applications where simplicity, reliability, and energy efficiency are important.

Electrical Holding Type Vacuum Contactor:
Operating Mechanism:Relies on an electrical holding coil to maintain the contacts in the closed position.
Advantages:Provides precise control over the contactor's status, and the contacts remain closed as long as the holding coil is energized.
Application:Commonly used in situations where precise control, remote operation, or coordination with other control systems is required.