Overview

The XGN66-12 fixed type enclosed switchgear (hereinafter referred to as switchgear) is a high-voltage power equipment product manufactured by our company. It complies with the requirements of the national standard GB3906 "3~35kV AC Metal-enclosed Switchgear", the power industry standard DL/T404 "Technical Conditions for Indoor AC High Voltage Switchgear Ordering", and also meets the requirements of IEC60298 "AC Metal-enclosed Switchgear and Controlgear for Rated Voltages Above 1kV and up to 52kV".

This product utilizes imported technology. It has a compact volume, which is only half the size of conventional switchgear. The circuit breaker features high reliability and good performance, and the "five-prevention" interlocking mechanism is reliable and simple. The switchgear is an indoor complete set device for 3.6, 7.2, and 12kV three-phase AC 50Hz single-busbar sections, used for the reception and distribution of electrical energy. It also possesses functions for circuit control, protection, and monitoring. It can be applied in various types of power plants, substations, industrial and mining enterprises, high-rise buildings, and other locations. It can also be combined with ring main units for application in open-type distribution stations.

Model Meaning

product-584-275

Normal Service Conditions

Altitude does not exceed 1000m.
Ambient temperature: -25℃ to +40℃, with the average temperature within 24 hours not exceeding +35℃.
Horizontal inclination is not greater than 3 degrees.
Earthquake intensity does not exceed magnitude 8.
No severe vibration, impact, or explosive and hazardous chemical environments.

Structural Features

The cabinet body is formed by angle steel welding.
The circuit breaker is located in the lower part of the cabinet, making installation, commissioning, and maintenance convenient. It is standardly equipped with a VS1 circuit breaker and comes with a pressure relief channel to ensure personnel safety.
An advanced and reliable rotary isolating switch is adopted, allowing safe entry into the circuit breaker compartment for maintenance while the main busbar is energized.
The protection grade of the entire cabinet is IP2X.
It is equipped with a highly functional and comprehensive forced mechanical interlocking device, which can simply and effectively meet the "Five-Prevention" (five-safety) requirements.
It is equipped with a reliable grounding system.
Observation windows are installed on the door, allowing a clear view of the working status of the components inside the cabinet.
The operating mechanism interlock adopts the JSXGN interlocking mechanism used in XGN2-12 cabinets, which is simple, reliable, and practical.
The incoming and outgoing cables are located at the lower front of the cabinet, providing easy connections for users.

Main Technical Parameters of Vacuum Circuit Breaker

Main Technical Parameters and Component Model Numbers of Switchgear

No.	Item	Unit	Technical Parameters
1	Rated voltage	kV	3.6, 7.2, 12
2	Rated power frequency withstand voltage	kV	To earth, between phases: 42; Across open contacts: 48
3	Rated lightning impulse withstand voltage	kV	To earth, between phases: 75; Across open contacts: 85
4	Rated frequency	Hz	50
5	Rated current	A	630, 1250
6	Rated short-circuit breaking current (RMS)	kA	20, 25, 31.5
7	Rated short-circuit making current (peak)	kA	50, 63, 80
8	Rated dynamic withstand current (peak)	kA	50, 63, 80
9	Rated thermal withstand current 4s (RMS)	kA	20, 25, 31.5
10	Protection class	-	IP2X
11	Overall dimensions (W×D×H)	mm	900×1000×2300
12	Weight	kg	≈ 600

Main Technical Parameters of QCE1-12 Model Vacuum Circuit Breaker

No.	Item	Unit	Technical Parameters
1	Rated voltage	kV	12
2	Rated current	A	630, 1250
3	Rated short-circuit breaking current	kA	20, 25, 31.5
4	Rated short-circuit making current	kA	50, 63, 80
5	Rated short-time withstand current (4s RMS)	kA	20, 25, 31.5
6	Rated peak withstand current (peak)	kA	50, 63, 80
7	Mechanical life	Times	10000
8	Number of breaking operations at rated short-circuit breaking current	Times	50
9	Rated operating sequence	-	O - 0.3s - CO - 180s - CO
10	Contact gap	mm	11±1
11	Contact overtravel	mm	4±0.5
12	Phase-to-phase center distance	mm	210
13	Opening speed	m/s	1.2±0.2
14	Closing speed	m/s	0.6±0.2
15	Opening time	ms	≤ 60
16	Closing time	ms	≤ 75
17	Three-phase opening simultaneity	ms	≤ 2
18	Closing bounce	ms	≤ 2
19	Circuit resistance	μΩ	≤ 45
20	Allowable cumulative contact wear thickness	mm	3

Footnotes:
◇ For technical parameters of other electrical components, please refer to their respective user manuals.
◇ For switchgear solutions with a rated current greater than 1600A, consultation with our company is required.

Installation

◆ Refer to the installation foundation diagram below. The foundation channel steel should protrude 1-3mm above the ground surface. The flatness should not exceed 1.5mm per meter and should not exceed 5mm over the total length.
◆ Place the switchgear on the foundation in sequence and adjust the installation position. Then, fix it using M12 bolts or spot welding. Tighten the adjacent cabinets together with M8 bolts.

◆ Remove the rear cover plates to install the main busbar and primary cables. The terminal contact surfaces should be cleaned thoroughly and coated with neutral Vaseline. After installation, seal the primary cable holes properly.
◆ Connect the grounding busbars between cabinets so that they form a continuous whole along the arrangement of the switchgear. Check that the working grounding and protective grounding are not omitted, and that the grounding circuit is continuously conductive. The working grounding resistance should not exceed 1000 μΩ, and the protective grounding resistance should not exceed 4 Ω.

◆ To install secondary cables, lead the cables in from the bottom front of the cabinet, run them along the side wall into the low-voltage compartment, and connect them to the terminal blocks; alternatively, lead them in from the secondary busbars at the top of the cabinet into the low-voltage compartment. Seal the cable holes after installation.
◆ Clean dust and debris inside the cabinet.

Commissioning

◆ The following inspections and commissioning tests should be performed prior to putting into operation:
◇ Check whether the models and specifications of the electrical components installed in the cabinet comply with the ordering requirements; check if the fasteners are loose; check if the primary and secondary wiring is correct; operate the isolating switch, earthing switch, circuit breaker, and mechanical interlock 3 to 5 times. They should operate flexibly without jamming. The interlocking must meet the "Five-Prevention" requirements. Then, apply lubricating grease to the mechanical moving parts.
◇ According to Article 3 of this manual and the factory test report, check the insulation level, loop resistance of the switchgear, and the mechanical characteristics of the circuit breaker. The test results should be consistent with or similar to the factory test report.

Maintenance and Overhaul

◆ Users should regularly perform maintenance and overhaul on the switchgear. The contents include:
◇ Clean dust from all parts, especially accumulated dust on the surfaces of insulating components;
◇ Inspect the mechanical moving parts and regularly apply lubricating grease to keep them flexible and reliable in operation;
◇ The maintenance of components such as circuit breakers, isolating switches, and earthing switches should be carried out in accordance with their respective instruction manuals;
◇ Check whether the electrical contact areas are in good condition, whether there is any overheating, and whether the earthing circuit is conductive;
◇ Regularly check if the fasteners are tightened.
◆ Users generally carry out troubleshooting with the assistance of the manufacturer. If it is only a minor adjustment or a small fault, the user should refer to this manual and the respective instruction manuals of the main components for self-repair.