I. Product Overview
This product is the TG4-10Q/128 (100×100) indoor high-voltage epoxy resin wall bushing. Manufactured using the epoxy resin APG (Automatic Pressure Gelation) process as a single-piece casting, it serves as a core insulation component for indoor complete power distribution equipment rated at 10kV and below. It is primarily used in high-voltage switchgear, ring main units (RMU), and withdrawable switchgear (KYN-type) to provide electrical insulation, mechanical support, and potential transition between live busbars/cables and the switchgear enclosure, thereby ensuring the safe and stable operation of the power distribution system.
II. Key Product Features
- Structural and Manufacturing Characteristics
- Monolithic Casting Structure: Cast as a single unit using the epoxy resin APG process; free of seams and air bubbles, ensuring uniform and stable insulation performance, high mechanical strength, and excellent resistance to impact and vibration.
- Optimized Shed Design: Features multiple sheds at both the top and bottom ends to effectively increase creepage distance and enhance resistance to pollution, moisture, and flashover, making it suitable for complex indoor environments such as those with high humidity or dust.
- Square Flange Mounting: Equipped with a 100×100mm square flange that fits standard switchgear mounting holes; allows for convenient installation and reliable sealing, effectively isolating the internal and external electrical spaces of the cabinet.
- Fully Insulated Design: The epoxy resin material offers excellent insulation properties with no risk of partial discharge; it resists aging and cracking during long-term operation, ensuring a long service life.
- Electrical Performance Characteristics
- Excellent dielectric strength and insulation resistance; meets long-term withstand voltage requirements for 10kV systems with extremely low partial discharge levels.
- Superior resistance to power-frequency and lightning impulse voltages; capable of withstanding system overvoltage surges without the risk of breakdown or flashover.
- Low dielectric loss and low dissipation factor; generates minimal heat during operation, eliminating the risk of thermal aging.
- Environmental and Operational Characteristics
- Resistant to pollution, moisture, and temperature extremes; operates reliably within a wide temperature range of -40°C to +65°C and requires no special maintenance for indoor installation.
- Excellent flame-retardant properties; complies with fire safety requirements for high-voltage electrical equipment, ensuring safety and reliability. • Maintenance-free design; requires only periodic surface cleaning to ensure long-term, stable operation.
III. Core Technical Parameters
| Parameter Category | Technical Specification | Description |
|---|---|---|
| Model and Specification | TG4-10Q/128(100×100) | Standard , 10kVSystem |
| Rated Voltage | 10kV(Maximum Operating Voltage12kV) | for10kV atIndoor System |
| Rated Frequency | 50/60Hz | Source specification |
| Overall Dimensions | 225mm, FlangeDimension100×100mm, Inner Hole /Cable | StandardMedium-Voltage Switchgear/Ring Main UnitInstallationDimension |
| Material | Epoxy Resin(APG | InsulationPerformance |
| Creepage Distance | ≥200mm | 10kVSystem |
| Power-Frequency Withstand Voltage | 42kV/1min | No Breakdown / No Flashover |
| Lightning Impulse Withstand Voltage | 75kV(Peak) | WithstandLightning VoltageImpulse |
| Partial Discharge | ≤5pC(10kVat) | PartialDischarge |
| Ambient Temperature | -40°C ~ +65°C | IndoorInstallationApplicable |
| Altitude | ≤2500m | 2500m |
| Mounting Method | Cable Inner Hole | Flange Securing |
IV. Scope of Application
- Application Scenarios
- Suitable for complete power distribution equipment such as 10kV indoor high-voltage switchgear (e.g., KYN28 metal-clad switchgear), Ring Main Units (RMU), box-type substations, and gas-insulated switchgear (GIS).
- Insulation and isolation within high-voltage cabinets for power distribution systems in power plants, substations, industrial/mining enterprises, and residential complexes.
- Serves as a wall-through insulation component for high-voltage busbars and cables, facilitating electrical connection and insulation isolation between the interior and exterior of the cabinet.
- Compatible Busbars/Cables
- Compatible with 100×100mm busbars; custom configurations (e.g., circular or cruciform apertures) are available to accommodate various copper busbar sizes and cable pass-through requirements. • Suitable for wall-penetrating transition connections of various high-voltage busbars and cables in 10kV systems.
V. Operating Conditions
- Normal Operating Conditions
- Ambient temperature: -40°C to +65°C; daily average temperature not exceeding +40°C.
- Altitude: Not exceeding 2500m (for altitudes above 2500m, insulation correction or customized products are required in accordance with standards).
- Environmental conditions: Indoor installation; free from severe pollution, corrosive gases, flammable or explosive media, and severe vibration.
- Relative humidity: Daily average relative humidity ≤95%; monthly average relative humidity ≤90%; no condensation.
- Installation angle: Can be installed vertically or horizontally; no specific angle restrictions.
- Special Operating Conditions (Customization Required)
- High-altitude, heavily polluted, high-humidity, or strong-vibration environments.
- Requirements for special temperatures, installation dimensions, or internal bore structures.
VI. Installation and Maintenance Requirements
- Installation Requirements
- Before installation, inspect the bushing’s appearance to ensure there are no cracks, damage, air bubbles, or deformation, and that the flange is flat.
- Pass the bushing through the cabinet’s mounting hole and secure it using the 100×100mm square flange and bolts; ensure a reliable seal and no looseness.
- Pass the busbar/cable through the bushing’s inner bore; ensure there is no contact or compression between the busbar and the inner wall of the bushing, and maintain sufficient insulation clearance.
- After installation, check the seal between the bushing and the cabinet to prevent moisture and dust from entering the cabinet.
- Upon completion of installation, perform a withstand voltage test; the unit may only be put into operation after confirming that insulation performance meets requirements.
- Maintenance Requirements
- Routine maintenance: Regularly inspect the bushing’s appearance for cracks, discharge marks, or signs of overheating.
- Cleaning and maintenance: Regularly clean dust and contaminants from the bushing surface to keep it clean and dry, preventing pollution flashover.
- Inspection and maintenance: During equipment servicing, check that connections between the bushing, busbar, and cabinet are secure and that the insulation remains intact. • Do not strike or impact the bushing; avoid mechanical damage that could lead to insulation failure.
VII. Precautions
- This product is designed for indoor use only; do not use it outdoors or in environments with high pollution or strong corrosive agents.
- Power must be disconnected during installation and maintenance; live work is strictly prohibited to prevent the risk of electric shock.
- If the bushing exhibits abnormalities such as cracks, damage, discharge marks, or overheating, the power must be disconnected immediately for replacement; continued use is prohibited.
- Handle with care during transport and storage; avoid impacts or crushing to prevent insulation damage.
- Installation and maintenance must be performed by qualified electrical personnel; operation by non-qualified personnel is prohibited.
VIII. Applicable Standards
This product complies with the following national/industry standards:
- GB/T 12944.1 “High-voltage wall bushings – Part 1: Porcelain and fiberglass bushings”
- GB/T 12944.2 “High-voltage wall bushings – Part 2: Indoor and outdoor epoxy resin bushings”
- DL/T 593 “Common technical requirements for high-voltage switchgear and controlgear standards”
