Product Overview
The JY JCTGZ-15/200 15kV 200A Insulated Bushing Extender is an extended-type cable accessory base designed specifically for 15kV (10kV class) medium-voltage power distribution systems. Constructed with an epoxy resin and rubber composite insulation structure, it provides an extended mounting base for elbow cable connectors and single-/double-ended bushing connectors, resolving issues of insufficient device interface clearance and restricted installation distance. It simultaneously provides insulation isolation, conductive connection, and protection functions, and is widely used in ring main units, compact substations, cable junction boxes, and other equipment. It is a critical extension component for constructing separable interfaces in medium-voltage distribution systems.
Product Features
Electrical and Insulation Performance
The main body is formed by epoxy resin casting combined with a rubber sealing structure, delivering excellent insulation performance. It withstands the rated voltage and short-duration overvoltages of a 15kV system, meeting the 17.5kV maximum operating voltage requirement of 10kV systems with adequate insulation margin.
An integrated electric field optimization structure uniformly distributes the electric field, effectively suppressing partial discharge. Long-term operation presents no risk of electrical erosion or breakdown; partial discharge level ≤10pC (at 1.5U₀).
The top-mounted copper terminal provides excellent conductivity with low contact resistance, capable of carrying a rated current of 200A with minimal heat generation during long-term operation, and offers strong anti-corrosion and anti-oxidation performance.
An integrated grounding connection structure enables reliable earthing, effectively dissipating fault currents and induced voltages to enhance system safety.
Structural and Safety Features
The integrated composite structure design provides high outer insulation strength; the housing may be touched directly during operation without risk of electric shock, ensuring the safety of operations and maintenance personnel.
The extended-length structural design provides additional installation distance, resolving insufficient device interface clearance and accommodating installation-space-constrained scenarios with a compact form that requires no extra equipment space.
Standardized interface design: both ends are compatible with 15kV 200A class standard interfaces — one end connects to the equipment bushing and the other to the cable accessory — offering high versatility and convenient installation.
The integrated rubber sealing structure achieves an IP67 protection rating, providing sealed isolation between equipment and accessories to prevent ingress of moisture and dust, enhancing the system’s moisture-proof and waterproof performance.
Anti-mismatching and anti-loosening design: standardized interface dimensions ensure compatibility only with accessories of the corresponding specification, eliminating the risk of incorrect connections or loose disconnections.
Environmental and Weather Resistance
Excellent weather resistance accommodates a wide operating temperature range of -40°C to +90°C; epoxy resin and rubber properties show no degradation at high or low temperatures with no risk of cracking or embrittlement, suitable for both outdoor and indoor applications.
Moisture-proof, waterproof, pollution-resistant, and salt-fog-resistant; capable of long-term stable operation in harsh environments including direct burial, high humidity, and dusty conditions, immune to rainwater and condensation corrosion.
Anti-aging, UV-resistant, and ozone-corrosion-resistant; service life exceeding 30 years with maintenance-free operation, reducing long-term operations and maintenance costs.
Mechanical and Compatibility Features
High mechanical strength with impact and vibration resistance; withstands mechanical stresses during transportation, installation, and operation with no risk of deformation or damage; seismic rating of Grade 8.
Compatible with 15kV 200A class standard cable accessory interfaces; interchangeable with same-specification elbow cable connectors, surge arresters, and grounding devices, offering strong compatibility.
Compact structure with flexible installation; adaptable to the installation spaces of mainstream distribution equipment such as ring main units, compact substations, and cable junction boxes, meeting extended installation requirements.
Technical Parameters
| Parameter Category | Item | Technical Specification |
| Rated Electrical Parameters | System Voltage (Un) | 10kV |
| | Rated Voltage (Ue) | 15kV | |
| | Maximum Operating Voltage (Um) | 17.5kV | |
| | Rated Current (Ie) | 200A | |
| | Rated Frequency (fn) | 50Hz/60Hz | |
| | Power Frequency Withstand Voltage | 42kV/5min (dry), 38kV/5min (wet), no breakdown, no flashover | |
| | Lightning Impulse Withstand Voltage | 95kV (peak), no breakdown, no flashover | |
| | Partial Discharge Level | ≤10pC (at 1.5U₀) | |
| | Rated Short-Circuit Withstand Current | 16kA/2s (20kA/2s optional, matched to system requirements) | |
| | Contact Resistance | ≤100μΩ | |
| Structural and Material Parameters | Main Body Material | Epoxy resin (insulation layer), tin-plated copper (conductive terminal), rubber (sealing element) |
| | Protection Rating | IP67 | |
| | Interface Standard | Both ends: 15kV 200A standard cable accessory interface | |
| | Grounding Method | Integrated grounding terminal for direct earthing connection | |
| | Extension Length | Customizable (standard specifications: 150mm/200mm; special lengths available on request) | |
| Environmental Parameters | Applicable Altitude | ≤2000m (high-altitude versions available on request) |
| | Ambient Temperature | -40°C to +90°C (operating), -40°C to +70°C (storage) | |
| | Relative Humidity | ≤100% (non-condensing) | |
| | Seismic Rating | Grade 8 | |
| Applicable Standards | IEEE 386, GB/T 12706, DL/T 404, GB/T 11022 |
Application Scope
Applicable voltage class: 10kV to 15kV AC medium-voltage distribution systems; compatible with equipment bushing interfaces rated at a maximum operating voltage of 17.5kV.
Applicable equipment and scenarios:
Bushing interface extension for 15kV ring main units, compact substations, cable junction boxes, American-style pad-mounted transformers, and other distribution equipment, resolving insufficient installation space;
Used in conjunction with elbow cable connectors, single-/double-ended bushing connectors, surge arresters, and grounding devices to construct extended separable cable terminations and arrester interfaces;
Urban distribution network cable lines, industrial and mining enterprise distribution systems, renewable energy (photovoltaic/wind power) step-up substation distribution interfaces;
Indoor/outdoor distribution rooms, underground utility tunnels, cable tunnels, and other installation-space-constrained scenarios requiring extended connections between equipment and accessories.
Functional purpose: Serves as an extended connection base between equipment bushings and cable accessories, providing insulation, sealing, conduction, and grounding connection, resolving insufficient installation space, and delivering a safe and reliable extended interface solution for distribution systems.
Operating Conditions
Normal Operating Conditions
Altitude: ≤2000m;
Ambient temperature: -40°C to +90°C; equipment operating temperature complies with relevant standards;
Relative humidity: ≤100% (non-condensing);
Environmental conditions: free from corrosive gases, flammable or explosive media, and severe vibration or shock;
Installation method: compatible with standard equipment bushing interfaces; horizontal or vertical installation permissible; installation space must satisfy the operational requirements of the associated accessories.
Special Operating Conditions (Customization Required)
Altitude exceeding 2000m;
Ambient temperature outside the range of -40°C to +90°C;
Severely polluted, salt-fog, or chemically corrosive environments;
High-vibration or high-impact operating conditions;
Non-standard equipment bushing interface specifications or special extension length requirements;
Special grounding requirements or high pollution severity level applications.
Installation and Maintenance
Installation Requirements
Before installation, inspect the product appearance for cracks, damage, or voids, and verify the insulating surface is undamaged; check that conductive terminals and sealing elements are intact, free of corrosion and aging.
Clean the equipment bushing interface surface, removing oil, dust, and foreign matter; ensure the interface is dry and clean.
Install the Insulated Bushing Extender onto the equipment bushing interface, ensuring full seating, engage the locking retention structure, and connect the grounding terminal to the earthing grid with a grounding resistance ≤4Ω.
Apply an even coat of dedicated silicone lubricant to the inner wall of the Insulated Bushing Extender output interface, then install the associated elbow connectors, bushing connectors, or other accessories, ensuring full seating and engaging the anti-withdrawal locking device.
After installation, perform insulation resistance testing and power frequency withstand voltage testing; the unit may be placed into service only upon passing these tests.
Maintenance Requirements
Periodically inspect the Insulated Bushing Extender appearance for cracks, discharge marks, or accumulated contamination; verify the grounding terminal connection is secure with no loosening, and that sealing elements show no aging or damage.
Periodically test insulation resistance to ensure performance meets requirements and to identify potential faults in a timely manner.
Clean the bushing extender surface, removing accumulated dust and contamination; keep the insulating surface dry and clean; avoid corrosion from oil or chemical substances.
If the bushing extender or associated accessories exhibit cracks, damage, discharge, abnormal heating, or other anomalies, immediately take out of service and replace; operation with known defects is strictly prohibited.
Insertion and withdrawal of associated accessories must be performed using dedicated insulating operating tools; bare-hand operation of energized connectors is strictly prohibited; all operations must strictly comply with distribution system safety regulations.
Precautions
The product must be installed, commissioned, and maintained by qualified electrical personnel holding medium-voltage distribution construction credentials; operation by non-qualified personnel is strictly prohibited.
The product must be used with equipment bushings and cable accessories of the corresponding specification; use with accessories of a different voltage class or current rating is strictly prohibited, as this will result in insulation failure and safety incidents.
The Insulated Bushing Extender must not be disassembled or modified without authorization, as this will void the warranty and safety assurance; use of non-dedicated tools to forcibly install or remove accessories is strictly prohibited.
During storage, the product must be kept in a dry, well-ventilated, cool environment, away from direct sunlight, high temperatures, moisture, and compressive loads; contact with sharp objects that could damage the insulation layer is strictly prohibited.
Live operation of associated accessories must strictly comply with distribution system safety regulations; appropriate safety protective measures must be taken; non-compliant operations are strictly prohibited.
Model Designation
| Model Identifier | Meaning |
|---|---|
| JY | Product series designation |
| JCTGZ | Insulated Bushing Extender series designation |
| 15/200 | Applicable system voltage class 15kV, rated current class 200A |
| Insulated Bushing Extender | Extended insulated bushing extender; serves as extended connection base for equipment bushing interfaces |
Applicable Standards and Certifications
International standard: IEEE 386, Standard for Separable Insulated Connector Systems for Power Distribution Systems Above 600V;
National standards: GB/T 12706, Power cables with extruded insulation and their accessories for rated voltages from 1kV (Um=1.2kV) up to 35kV (Um=40.5kV); GB/T 11022, Common specifications for high-voltage switchgear and controlgear standards; DL/T 404, 3.6kV~40.5kV AC metal-enclosed switchgear and controlgear;
The product has passed type testing by the National High-Voltage Electrical Apparatus Quality Supervision and Inspection Center and complies with national electrical safety standards.
After-Sales Service
Product warranty period: 18 months from the date of manufacture, or 12 months from the date of commissioning, whichever occurs first;
During the warranty period, products with quality defects are repaired or replaced free of charge;
Technical support, installation guidance, and customization services are available (special extension lengths, special operating condition adaptation).
Documentation Notes
The technical parameters in this manual are based on standard operating conditions. Special operating conditions require customization according to actual requirements. The product technical agreement and type test report shall prevail as the final reference.
