Product Overview
The JDZW-10 Voltage Transformer is a fully enclosed, dry-type cast-resin voltage transformer designed for outdoor 10 kV AC power systems with a maximum system voltage of 12 kV.
The product features an integrated epoxy resin cast insulation structure with excellent resistance to pollution flashover and outdoor weather conditions. Its magnetic core is made of high-quality laminated silicon steel sheets, while the windings are wound with enamelled copper wire.
The JDZW-10 is mainly used for voltage measurement, energy metering, relay protection, and insulation monitoring in outdoor power distribution equipment, pole-mounted distribution systems, box-type substations, outdoor ring main units, and other 10 kV electrical installations.
Product Features
Insulation and Electrical Performance
- Fully enclosed epoxy resin cast insulation:
The transformer is manufactured using an integrated epoxy resin vacuum-casting process. The solid insulation body contains no internal air gaps and provides excellent dielectric performance. It can withstand the operating voltage, power-frequency withstand voltage, and lightning impulse withstand voltage requirements of 12 kV systems. - Oil-free dry-type design:
The product contains no insulating oil, eliminating the risks of oil leakage, oil contamination, and oil-related fire hazards. It is suitable for modern outdoor oil-free power distribution systems. - Multiple voltage ratios:
Voltage ratios such as 10/0.1 kV and 10/0.1/0.1 kV are available. Multiple secondary outputs can be provided simultaneously for metering, protection, and insulation-monitoring circuits. - Multiple accuracy classes:
Metering accuracy classes of 0.2, 0.5, and 1 and protection accuracy classes of 3P and 6P can be supplied according to application requirements. - High insulation and pollution-flashover resistance:
The high-voltage terminals feature a multi-shed insulation structure that increases the creepage distance and improves resistance to surface flashover under polluted and humid outdoor conditions. - Low partial discharge:
The advanced casting process limits partial discharge to no more than 10 pC, helping reduce insulation ageing and improve long-term operating reliability.
Structural and Installation Features
- Fully enclosed outdoor structure:
The magnetic core, windings, and live components are enclosed within the cast insulation body. The product provides an IP34 protection rating and can be used in exposed outdoor environments. - Rainproof and pollution-resistant design:
The housing is designed to resist rain, contamination, and condensation while maintaining reliable insulation performance. - Compact modular construction:
The compact structure is suitable for outdoor distribution equipment and pole-mounted installations. Horizontal and vertical mounting configurations are available. - Clearly identified terminals:
The high-voltage terminals are clearly marked, while the low-voltage terminals are protected by a waterproof terminal cover. This simplifies wiring and helps prevent incorrect connections, short circuits, and water ingress. - Flexible installation:
The metal mounting base includes fixing holes for secure bolt installation. The structure provides reliable resistance to vibration and wind loads in outdoor applications.
Operation and Maintenance Features
- Low-maintenance operation:
The dry-type, oil-free construction eliminates leakage and oil-related fire risks. The epoxy resin body provides high mechanical strength, impact resistance, ageing resistance, and weather resistance. - Outdoor environmental durability:
The product can withstand ultraviolet exposure, outdoor temperature variations, rain, and normal atmospheric pollution. - Wide operating temperature range:
The transformer can operate at ambient temperatures from -40°C to +70°C. The epoxy resin maintains stable mechanical and insulation performance without becoming brittle or deformed. - High-reliability design:
The enamelled copper windings and high-quality laminated silicon steel core provide low operating losses, limited temperature rise, and stable accuracy. - Overvoltage withstand capability:
The transformer can withstand switching and lightning overvoltages within its specified insulation level, ensuring stable metering and protection signals.
Technical Specifications
Electrical Parameters
| Parameter | Specification |
|---|---|
| Applicable System Voltage | 10 kV AC, Um = 12 kV |
| Rated Frequency | 50 Hz |
| Rated Primary Voltage | 10 kV |
| Rated Secondary Voltage | 100 V for metering and protection; 100/3 V for optional insulation monitoring |
| Metering Accuracy Class | Class 0.2 / 0.5 / 1 |
| Protection Accuracy Class | 3P / 6P |
| Power-Frequency Withstand Voltage | 42 kV for 1 minute at the high-voltage terminal, without breakdown |
| Lightning Impulse Withstand Voltage | 75 kV peak, without breakdown |
| Partial Discharge | ≤10 pC |
| Insulation Resistance | ≥1,000 MΩ between the high-voltage winding, low-voltage winding, and earth |
Structural and Material Parameters
| Parameter | Specification |
|---|---|
| Insulating Medium | Fully cast epoxy resin |
| Protection Rating | IP34 |
| Installation Type | Outdoor post-type or pole-mounted bolt installation |
| Thermal Class | Class B, 130°C |
Environmental Parameters
| Parameter | Specification |
|---|---|
| Installation Altitude | ≤2,000 m; high-altitude versions available |
| Operating Temperature | -40°C to +70°C |
| Storage Temperature | -40°C to +85°C |
| Relative Humidity | ≤95%, non-condensing |
Applicable Standards
| Standard | Description |
|---|---|
| GB 1207 | Voltage Transformers |
| GB/T 20840.1 | Instrument Transformers—Part 1: General Requirements |
| GB/T 20840.3 | Instrument Transformers—Part 3: Additional Requirements for Inductive Voltage Transformers |
Applications
Applicable Voltage Level
The JDZW-10 Voltage Transformer is suitable for outdoor 10 kV AC power systems with a maximum system voltage of 12 kV.
Typical Applications
- Voltage measurement, energy metering, and relay protection in outdoor power distribution equipment
- Pole-mounted power distribution systems
- Voltage monitoring and insulation supervision in box-type substations
- Outdoor ring main units and switching stations
- Outdoor 10 kV power distribution systems in industrial and mining enterprises
- Commercial buildings and industrial parks
- Voltage monitoring, control, and protection signal acquisition in power automation systems
- Polluted, humid, and exposed outdoor distribution environments requiring high weather resistance and pollution-flashover protection
Main Functions
The voltage transformer converts the system high voltage into a standardized secondary voltage, typically 100 V, at a specified ratio.
It supplies voltage signals to:
- Energy meters
- Measuring instruments
- Relay protection devices
- Monitoring equipment
- Control systems
- Insulation monitoring devices
The transformer also provides electrical isolation between the primary and secondary systems, helping protect connected equipment and operating personnel.
When equipped with an auxiliary secondary winding, it can provide a voltage signal for insulation monitoring and system earth-fault detection.
Operating Conditions
Normal Operating Conditions
- Installation altitude: no more than 2,000 m
- Ambient temperature: -40°C to +70°C
- Severe or sudden temperature changes should be avoided
- Relative humidity: no more than 95%, non-condensing
- The environment should be free from corrosive gases
- Flammable or explosive substances are not permitted
- Severe vibration and mechanical impact should be avoided
- The product can withstand normal outdoor wind, rain, humidity, and pollution
- The installation location should be well ventilated and free from standing water or prolonged immersion
- Outdoor post-type or pole-mounted installation
Special Operating Conditions
Customized products are required for:
- Installation altitudes above 2,000 m
- Ambient temperatures outside the range of -40°C to +70°C
- Severe pollution or salt-spray environments
- Chemically corrosive environments
- Applications involving strong vibration or mechanical impact
- Non-standard voltage ratios
- Special accuracy classes
- Non-standard mounting dimensions
Installation and Maintenance
Installation Requirements
- Pre-installation inspection:
Inspect the voltage transformer and confirm that the cast body is free from cracks, bubbles, mechanical damage, and other visible defects. Check that the terminal markings are clear and that all accessories are complete. Verify that the model, specifications, voltage ratio, and accuracy class match the system design requirements. Confirm that the pollution-resistant shed structure is complete and undamaged. - Mounting:
Position the voltage transformer at the specified installation location and secure it with bolts through the mounting holes in the base. Ensure that the transformer is firmly installed without looseness or displacement. The mounting surface should be level to avoid uneven mechanical stress. Outdoor installations must include suitable waterproofing and drainage measures. Pole-mounted installations must be securely fixed to prevent movement under wind or vibration. - High-voltage-side connection:
Connect the high-voltage terminal according to the system design. Ensure that the connection is secure and provides reliable electrical contact. Maintain adequate electrical clearance between the high-voltage conductor, grounded components, and other live parts. Use suitable waterproof insulated conductors and seal outdoor connections against water ingress. - Low-voltage-side connection:
Connect the secondary terminals according to their markings. Metering, protection, and insulation-monitoring circuits must be wired separately and correctly. The secondary circuit must not be short-circuited during operation. One point of the secondary circuit must be reliably grounded according to the system design and applicable electrical safety requirements. The low-voltage terminals must be properly protected and sealed against moisture. - Insulation inspection:
After installation, measure the insulation resistance between:- High-voltage winding and low-voltage winding
- High-voltage winding and earth
- Low-voltage winding and earth
Maintenance Requirements
- Regularly inspect the epoxy resin body for cracks, mechanical damage, discharge marks, and contamination.
- Check the high-voltage terminals for looseness, oxidation, or abnormal heating.
- Inspect the insulating sheds for accumulated dust and pollution.
- Pay particular attention to the pollution-resistant structure and sealing condition.
- Regularly inspect the high-voltage and low-voltage wiring to ensure that all connections remain secure and free from overheating or discoloration.
- Check that the low-voltage terminal cover and waterproof seals remain intact.
- Confirm that the secondary-circuit grounding remains reliable.
- Periodically test the insulation resistance and voltage ratio to verify that the metering and protection accuracy remain within the specified limits.
- Check the insulation-monitoring function where an auxiliary winding is provided.
- Regularly clean dust and contamination from the transformer surface and insulating sheds to reduce the risk of pollution flashover.
- Prevent oil and corrosive substances from contacting the epoxy resin body.
- If cracking, discharge, overheating, or excessive voltage-ratio error is detected, immediately de-energize and inspect the equipment. Replace the transformer where necessary.
Precautions
- The secondary winding must not be short-circuited while the transformer is energized. A secondary short circuit may produce excessive current and create a serious risk to equipment and personnel. During maintenance, the transformer must be de-energized, and the secondary circuit must be safely isolated and grounded in accordance with applicable procedures.
- Avoid impact or collision with the epoxy resin body, high-voltage terminals, and insulating sheds during transportation and installation. Mechanical damage may reduce insulation performance and pollution-flashover resistance.
- Use suitable insulated conductors for high-voltage connections. Maintain adequate electrical clearance from grounded components and other live parts to prevent phase-to-phase or phase-to-earth discharge.
- Outdoor connections must be properly sealed to prevent rainwater and moisture ingress.
- The equipment must be reliably grounded. The grounding terminal on the metal base must be securely connected to the grounding busbar.
- Store the product in a dry, ventilated, and shaded environment. Avoid direct sunlight, high temperatures, moisture, compression, and mechanical impact. Long-term storage requires suitable moisture and corrosion protection.
- Installation, commissioning, and maintenance must be carried out by qualified electrical personnel in accordance with applicable electrical safety procedures.
Standard Supply List
| No. | Item | Function |
|---|---|---|
| 1 | JDZW-10 Voltage Transformer | Main device for voltage transformation, electrical isolation, and signal acquisition |
| 2 | Mounting Bolts and Washers | Used to secure the voltage transformer during installation |
| 3 | Waterproof Low-Voltage Terminal Cover | Protects the secondary terminals against incorrect connection, short circuits, and water ingress |
| 4 | Product Instruction Manual | Provides installation, operating, maintenance, and outdoor mounting guidance |
| 5 | Product Certificate and Factory Test Report | Provides product quality and performance documentation, including voltage-ratio and accuracy test data |
Applicable Standards and Certification
The product complies with the following standards:
- GB 1207, Voltage Transformers
- GB/T 20840.1, Instrument Transformers—Part 1: General Requirements
- GB/T 20840.3, Instrument Transformers—Part 3: Additional Requirements for Inductive Voltage Transformers
The product has passed the applicable type tests, and its performance meets the operating requirements of outdoor 10 kV power systems.
