I. Product Overview
The JY TGZ-200 15kV/24kV 200A Casing Seat is a cable accessory base specifically designed for 15kV/24kV medium-voltage power distribution systems. It employs an epoxy resin and rubber composite insulation structure and serves as the installation base for elbow-type cable joints and single/double-pass bushing joints. It achieves insulated and sealed connections between equipment bushings and cable accessories, and also functions as a grounding and conductive connection. It is widely used in ring main units, prefabricated substations, cable branch boxes, and other equipment, and is a key component in constructing separable interfaces for medium-voltage power distribution systems.
II. Product Characteristics
1. Electrical and insulation properties
- The main body is made of epoxy resin casting and combined with a rubber sealing structure, which has excellent insulation performance. It can withstand the rated voltage of 15kV/24kV system and short-time overvoltage, meet the operating requirements of the maximum working voltage of 17.5kV/24kV, and has sufficient insulation margin.
- With a built-in optimized electric field structure, the electric field is evenly distributed, effectively suppressing partial discharge. There is no risk of electrical erosion or breakdown during long-term operation, and the partial discharge amount is ≤10pC (below 1.5U₀).
- The top uses copper terminals, which have excellent conductivity, low contact resistance, can carry a rated current of 200A, generate little heat during long-term operation, and have strong corrosion and oxidation resistance.
- It has a built-in grounding connection structure, which can achieve reliable grounding, effectively release fault current and induced voltage, and improve system safety.
2. Structural and Safety Features
- The integrated composite structure design has high outer insulation strength, allowing direct contact with the outer shell during operation without the risk of electric shock, thus ensuring the safety of maintenance personnel.
- The standardized interface design is compatible with 15kV/24kV 200A grade elbow cable joints and single/double through bushing joints, making it highly versatile and easy to install.
- With its own rubber sealing structure and IP67 protection rating, it can achieve sealed isolation between the equipment and accessories, preventing moisture and dust from entering and improving the system’s moisture-proof and waterproof performance.
- The design prevents misconnection and loosening, and the interface size is standardized, so it can only be matched with accessories of the corresponding specifications, eliminating the risk of misconnection, loosening and falling off.
3. Environmental and Weather Resistance
- With excellent weather resistance, it can adapt to a wide temperature range of -40℃ to +90℃. The performance of epoxy resin and rubber does not degrade under high and low temperatures, and there is no risk of cracking or embrittlement. It is suitable for various outdoor and indoor scenarios.
- It is moisture-proof, waterproof, stain-proof, and salt spray-proof, and can operate stably for a long time in harsh environments such as underground, damp, and dusty conditions, and is not afraid of rain or condensation.
- It is resistant to aging, ultraviolet rays, and ozone corrosion, with a service life of over 30 years. It requires no maintenance and reduces subsequent operation and maintenance costs.
4. Mechanical and Adaptation Characteristics
- It has high mechanical strength, is impact and vibration resistant, and can withstand mechanical stress during transportation, installation and operation without deformation or damage risk. Its seismic resistance level reaches level 8.
- It is compatible with 15kV/24kV 200A standard cable accessory interfaces and can be interchanged with elbow-type cable joints, surge arresters, and grounding devices of the same specifications, with strong compatibility.
- With its compact structure and flexible installation method, it can be adapted to the installation space of mainstream power distribution equipment such as ring main units, prefabricated substations, and cable branch boxes.
III. Technical Parameters
| Parameter categories | project | Technical indicators |
| Rated electrical parameters | Rated voltage (Ue) | 15kV/24kV (Applicable to 10kV/20kV systems, maximum operating voltage 17.5kV/24kV) |
| Rated current (Ie) | 200A | |
| Rated frequency (fn) | 50Hz/60Hz | |
| Power frequency withstand voltage | 42kV/5min (15kV dry test), 65kV/5min (24kV dry test), no breakdown, no flashover. | |
| Lightning impulse withstand voltage | 95kV (15kV peak) and 125kV (24kV peak), no breakdown and no flashover. | |
| Partial discharge quantity | ≤10pC (below 1.5U₀) | |
| Rated short-circuit withstand current | 16kA/2s (20kA/2s optional, depending on system requirements) | |
| Contact resistance | ≤100μΩ | |
| Structural and material parameters | Main material | Epoxy resin (insulating layer), tin-plated copper (conductive terminals), rubber (sealing components) |
| Protection level | IP67 | |
| Interface Standard | 15kV/24kV 200A Standard Cable Accessory Interface | |
| grounding method | It has a built-in grounding connection terminal and can be directly grounded. | |
| Environmental parameters | Applicable altitude | ≤2000m (Customization available for high altitudes) |
| Ambient temperature | -40℃/ +90℃ (operating temperature), -40℃/ +70℃ (storage temperature) | |
| relative humidity | ≤100% (no condensation) | |
| Seismic resistance level | Level 8 | |
| Implementation Standards | IEEE 386, GB/T 12706, DL/T 404, GB/T 11022 |
IV. Scope of Application
- Applicable voltage levels : 10kV/ 15kV/20kV/ 24kV AC medium voltage power distribution systems, compatible with equipment bushing interfaces with a maximum operating voltage of 17.5kV/24kV.
- Applicable equipment scenarios :
- Bushing interface bases for power distribution equipment such as 15kV/24kV ring main units, prefabricated substations, cable branch boxes, and American-style prefabricated substations;
- It can be used in conjunction with elbow-type cable joints, single/double bushing joints, surge arresters, and grounding devices to construct a complete detachable cable terminal and surge arrester interface;
- Urban power distribution network cable lines, power distribution systems of industrial and mining enterprises, and power distribution interfaces for new energy (photovoltaic/wind power) booster stations;
- Insulated connection base for equipment sleeves in various scenarios such as indoor/outdoor power distribution rooms, underground pipe corridors, and cable tunnels.
- Function and application : As a connection base for equipment bushings and cable accessories, it realizes insulation, sealing, conductivity and grounding connection, and provides a safe and reliable interface base solution for power distribution systems.
V. Usage Conditions
1. Normal operating conditions
- Altitude: ≤2000m;
- Ambient temperature: -40℃~+90℃; equipment operating temperature complies with relevant standards.
- Relative humidity: ≤100% (no condensation);
- Environmental conditions: No corrosive gases, no flammable or explosive media, no severe vibration or impact;
- Installation method: It is compatible with standard equipment sleeve interfaces and can be installed horizontally or vertically. The installation space must meet the operation requirements of the accessories.
2. Special usage conditions (customization required)
- The altitude exceeds 2000m;
- The ambient temperature exceeds the range of -40℃ to +90℃;
- Severely polluted, salt spray, and chemically corrosive environments;
- High vibration and high impact conditions;
- Non-standard equipment sleeve interface specifications;
- Special grounding requirements and high pollution levels.
VI. Installation and Maintenance
1. Installation Requirements
- Before installation, inspect the product appearance for cracks, damage, bubbles, and undamaged insulation surfaces; check that conductive terminals and seals are intact and free from rust and aging.
- Clean the surface of the equipment sleeve interface to remove oil, dust, and foreign objects, ensuring the interface is dry and clean.
- Install the bushing seat to the equipment bushing interface, ensuring proper installation, lock the fixed structure, and connect the grounding terminal to the grounding grid. The grounding resistance should be ≤4Ω.
- Apply special silicone grease lubricant evenly to the inner wall of the sleeve seat interface, and then install the matching elbow joint, sleeve joint and other accessories, ensuring that the accessories are installed in place and locking the anti-detachment device.
- After installation, insulation resistance and power frequency withstand voltage tests are conducted. Only after passing these tests can the equipment be put into operation.
2. Maintenance Requirements
- Regularly inspect the appearance of the bushing socket; check for cracks, discharge marks, and dirt accumulation; ensure the grounding terminal connection is secure and not loose; and ensure the seals are free from aging or damage.
- Regularly test the insulation resistance to ensure that the performance meets the requirements and to detect potential faults in a timely manner.
- Clean the surface of the bushing socket to remove accumulated dust and dirt, and keep the insulation surface dry and clean to avoid corrosion from oil and chemicals.
- If the bushing seat or its accessories show abnormalities such as cracks, damage, discharge, or overheating, stop using it immediately and replace it. It is strictly forbidden to operate it with defects.
- Special insulated tools must be used for plugging and unplugging accessories. It is strictly forbidden to operate live connectors by hand. Power distribution safety regulations must be strictly followed during operation.
VII. Precautions
- The product must be installed, debugged, and maintained by professional electrical personnel with medium-voltage power distribution construction qualifications. Operation by non-professional personnel is strictly prohibited.
- The product must be used with the corresponding specifications of equipment sleeves and cable accessories. It is strictly forbidden to use accessories of different voltage levels or current levels, otherwise it will lead to insulation failure and safety accidents.
- The sleeve socket must not be disassembled or modified without authorization, otherwise the warranty and safety guarantee will be lost. It is strictly forbidden to use non-special tools to forcibly install or disassemble the accessories.
- When storing, it should be placed in a dry, ventilated, and cool environment, avoiding direct sunlight, high temperature, humidity, and compression. It is strictly forbidden to contact with sharp objects that may damage the insulation layer.
- When operating accessories on live circuits, it is essential to strictly adhere to power distribution safety regulations, implement appropriate safety precautions, and strictly prohibit any unauthorized operations.
VIII. Model Description
| Model Identification | meaning |
| JY | Product series code |
| TGZ | Sleeve seat series code |
| □ | Voltage levels (15/24, representing 15kV/24kV respectively) |
| 200 | Rated current rating, compatible with 200A current rating |
| Casing seat | Sleeve base, a mounting base for cable accessories used for equipment sleeve interfaces. |
IX. Implementation Standards and Certification
- International Standard: IEEE 386 “Medium Voltage Detachable Cable Connector Standard”;
- National standards: GB/T 12706 “Extruded insulated power cables and accessories with rated voltage of 1kV (Um=1.2kV) to 35kV (Um=40.5kV)”, GB/T 11022 “Common technical requirements for high voltage switchgear and controlgear standards”, DL/T 404 “3.6kV~40.5kV AC metal-enclosed switchgear and controlgear”;
- The product has passed the type test of the National High Voltage Electrical Apparatus Quality Supervision and Inspection Center and meets national electrical safety standards.
X. After-sales service
- Product warranty period: 18 months from the date of manufacture, or 12 months from the date of commissioning (whichever comes first).
- During the warranty period, products will be repaired or replaced free of charge if quality issues arise.
- We provide technical support, installation guidance, and customized services (adaptation to special specifications and working conditions).
Document Description
The technical parameters in this manual are based on standard operating conditions. Special operating conditions need to be customized according to actual needs. The final specifications shall be subject to the product technical agreement and type test report.
Appendix: Product outline diagram
