GW7B-252D(G)252kV Outdoor high-voltage AC isolation switchDetailed product description：

GW7B-252D (G) type outdoor high-voltage transmission equipment with a three-phase AC frequency of 50Hz is used to disconnect or connect high-voltage lines under no-load conditions, in order to switch high-voltage lines, change operating modes, and safely isolate high-voltage electrical equipment such as busbars and circuit breakers for maintenance.
This product is a three column horizontal fracture switch flip type, which can be equipped with JW10-252 grounding switches on one or both sides. The isolation switch adopts SRCJ2 type motor operating mechanism three pole linkage operation; The grounding switch adopts SRCS1 type manual operation mechanism with three pole linkage operation.

The GW7B-252D (G) 252kV outdoor high-voltage AC isolation switch complies with standards such as GB1985-2004 "High Voltage AC Isolation Switches and Grounding Switches", GB11022-1999, DL/T593-2006 "Common Technical Requirements for High Voltage Switchgear and Control Equipment Standards", DL/T486-2000 "Technical Conditions for Ordering AC Isolation Switches and Grounding Switches", and meets the relevant regulations on ordering high-voltage isolation switches issued by State Grid Corporation of China for improvement. And through seismic resistance calculation analysis with a seismic intensity of 9 degrees.

The GW7B-252D (G) 252kV outdoor high-voltage AC isolation switch adopts a flip type, with a two-step action of the conductive tube. When closing, the conductive tube first rotates about 70 ° on the horizontal plane. When the two end contacts enter the static contact seat and are blocked, the flipping mechanism drives the conductive tube to rotate about 45 °. The moving contact is in reliable contact with the contact finger, with low operating force and no impact force on the fixed insulators at both ends. The main contact has self cleaning ability.
The U-shaped contact finger in the static contact is fixed at one end on the contact seat, forming a fixed connection and ensuring reliable conductivity; The other end generates contact pressure on the moving contact through an external pressure spring and the elastic force of the contact finger itself, and automatically increases the clamping force when the short-circuit current passes through. The touch finger spring is made of stainless steel material and has an insulating spacer, which prevents rusting and prevents flow diversion.
The static contact is equipped with a hook plate, which locks the moving contact after closing. Even under strong winds, vibrations, and electric forces, the contact will not detach. The arcing contacts on the dynamic and static contacts enable the isolation switch to have good performance in switching busbar current and switching capacitors and inductors with low current.
The grounding switch is a one-step action type, with a simple structure and easy maintenance. It effectively uses electric force to clamp the contacts and keep the grounding knife in the closed position. It has strong ability to withstand short-circuit currents and high parameters for opening and closing induced currents.
The conductive tube is made of high-strength, high conductivity, and corrosion-resistant aluminum material. The two end moving contacts are assembled and easy to replace.
The conductive tube flipping mechanism is enclosed, rainproof, dust-proof, and corrosion-resistant, and the flipping action is accurate and reliable.
The base is made of square steel pipes and bent plates welded together, with high strength and good rigidity. The surface is hot-dip galvanized and has strong anti-corrosion ability. All black metal components (including M10 and above fasteners) are treated with hot-dip galvanizing.
The rotating parts of the isolation switch are designed according to maintenance free requirements. The rotating seat is a fully sealed structure, which prevents water vapor, dust, and harmful gases from entering. The lubricating grease inside the bearing does not lose or solidify.
Stainless steel pin shafts, self-lubricating bearings, and stainless steel joint bearings are used at each rotating friction point.
The transmission connecting rod adopts assembly type, and on-site installation does not require cutting and welding. The connecting rod adopts hot-dip galvanized seamless steel pipe.
The mechanism interlocking between the main blade and the ground blade adopts a cam sliding plate structure, with direct action and reliable interlocking.
The operating mechanism box is made of stainless steel plate riveting, which does not require welding and has a good appearance. The electric mechanism adopts a hollow gearbox and nylon gears, with smooth and noise free operation. It uses foreign brand electrical components, which work reliably and have complete locking functions.
The human resources organization utilizes the intermediate relay installed in the box to achieve electromagnetic lock function, which is reliable in interlocking and overcomes the disadvantages of rust, corrosion, and malfunction of outdoor electromagnetic locks commonly used in China.

project			Unit	Parameters
rated voltage			kV	two hundred and fifty-two
Rated insulation level（1）	a) 1-minute power frequency withstand voltage (effective value)		kV	to the ground	four hundred and sixty
			kV	fracture	five hundred and thirty
	The shortest distance during the closing process of the grounding switch		kV	two hundred and ninety-one
	b) Rated lightning impulse withstand voltage (peak)		kV	to the ground	one thousand and fifty
			kV	fracture	one thousand and two hundred
rated frequency			Hz	fifty
rated current			A	2000  2500  3150  4000
Rated short-time withstand current			kA	fifty
Rated peak withstand current			kA	one hundred and twenty-five
Rated short-circuit duration			s	three
Rated terminal mechanical load		Horizontal and vertical loads	N	one thousand and five hundred
		Horizontal lateral load	N	one thousand
		vertical force	N	one thousand two hundred and fifty
Isolation switch busbar conversion current opening and closing capability				300V, 1600A, 100 times
Grounding switch induced current opening and closing capability		1) Electromagnetic induction current (current/voltage)	A/kV	160/15（2） （80/2）
		2) Static induced current (current/voltage)	A/kV	10/15（2） （3/12）
		3) Opening and closing times	time	ten
Isolation switch low current opening and closing capability		capacitive current	A	one
		Inductive current	A	zero point five
mechanical life			time	two thousand
creepage distance			mm	6300     7812
Human operated mechanism		model		SRCS1
		Control circuit voltage	V	AC220
Electric motor operating mechanism		model		SRCJ2
		Motor voltage	V	AC380
		Control circuit voltage	V	AC220
		Opening and closing time	s	14±1
		output angle		180°
unipolar weight		not grounded	kg	six hundred and thirty
		Single grounding	kg	six hundred and fifty
		Double grounding	kg	six hundred and seventy
Note: (1) This product belongs to the high-altitude (G) type, and the insulation test is assessed at an altitude of 2000 meters, with a correction factor of k=1.13; If the insulation level is set at 395 kV, it can be used in areas with an altitude of 2800 meters. (2) The parameters are specified as Class B values in DL/T486-2000, and arc ignition devices must be installed; The values in parentheses are specified for Class B in GB1985-2004.