Overview
The JDZW-35R/280 and JDZX(F)W-35R are outdoor single-phase epoxy cast-resin voltage transformers designed for 35kV systems, featuring integrated fuse protection. The epoxy cast-resin insulation ensures maintenance-free operation and a compact footprint compared to traditional oil-immersed types.
Available in multiple accuracy classes (0.2, 0.5, 1.0, 3P, 6P), these units support applications ranging from precision metering to protective relaying. They comply with GB20840.1-2010 and GB20840.3-2013 standards and operate reliably in ambient temperatures from -25°C to +40°C. Typical uses include outdoor substations, transmission networks, and industrial or renewable energy facilities requiring robust, low-maintenance voltage measurement.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System Voltage | 35kV |
| Primary Voltage | 35kV or 35/√3 kV |
| Secondary Voltage | 0.1kV, 0.1/√3 kV, or 0.1/3 kV |
| Thermal Limit Output | 1000VA |
| Accuracy Classes | 0.2, 0.5, 1.0, 3P, 6P |
| Insulation Type | Epoxy cast-resin |
| Fuse Protection | Built-in |
| Phase | Single-phase |
| Installation | Outdoor |
| Ambient Temperature Range | -25°C to +40°C |
| Standards | GB20840.1-2010, GB20840.3-2013 |
| Residual Winding | JDZX(F)W model only |
Construction
The transformer features a monolithic epoxy cast-resin construction, encapsulating all active components in a solid, weather-resistant housing. This design eliminates the need for oil or gas insulation, providing inherent resistance to moisture, pollution, and UV exposure. The primary and secondary windings are fully embedded within the epoxy matrix, ensuring excellent dielectric strength and mechanical stability. The built-in high-voltage fuse is integrated into the primary winding assembly, offering reliable overcurrent protection without external hardware. Terminal connections are housed in protected chambers with creepage distances optimized for outdoor service in polluted environments. The entire unit is mounted on a robust base suitable for concrete foundation installation, with provisions for secure grounding and safe maintenance access.
Technical Parameters
Service Conditions
- Installation position: Outdoor substations, switching stations, or transmission networks
- Ambient temperature: -25°C to +40°C
- Altitude: ≤ 1000m (standard), higher altitude available on request
- Insulation: Epoxy cast-resin (maintenance-free)
- Frequency: 50Hz or 60Hz
- Phase configuration: Single-phase (use three units for three-phase systems)
- Protection: Built-in fuse (integrated overcurrent protection)
- Maintenance: Maintenance-free operation (no periodic oil testing required)
Technical Parameters
The JDZW-35R/280 and JDZX(F)W-35R series are outdoor single-phase epoxy cast-resin voltage transformers rated for 35kV systems with integrated fuse protection. They operate within an ambient temperature range of -25°C to +40°C at altitudes up to 1000m, comply with GB20840.1-2010 and GB20840.3-2013 standards, and support both 50Hz and 60Hz frequencies.
| Type | Rated
Voltage (kV) |
Rated insulation
(kV) |
Accuracy class /
Rated output (VA) |
Max.
output (VA) |
|---|---|---|---|---|
| JDZW-35R | 35/0.1 | 40.5/95/200 | 0.2 50 0.5 100 1 200 |
1000 |
| 35/0.1/0.1 | 0.2/0.5 30/40 | 2*500 | ||
| JDZX(F)W-35R | 35/√3/0.1/√3/0.1/3 | 40.5/95/200 | 0.2(0.5)/3P(6P) 30(60)/100 | 600 |
| 35/√3/0.1/√3/0.1/√3/0.1/3 | 0.2/0.5/3P(6P) 15/20/100 0.2/0.2/3P(6P) 15/15/100 |
2*300 |
Installation & Wiring
Outline Dimensions
Overall dimensions: Height approximately 850+10mm, Top width 642.5mm, Base width 445mm, Footprint 758×510mm. Weight: approximately 126kg. Mounting is provided via base mounting feet with bolt holes. The insulator is arranged in a 22.5° V-configuration. Maintain a minimum clearance of 600mm around the transformer for maintenance access.
Wiring Diagram
The JDZW-35R/280 and JDZX(F)W-35R support multiple wiring configurations: Star connection (Y) for standard voltage measurement, or Star connection with residual winding for ground fault detection. Primary terminals A, B, C connect to the 35kV system. Secondary outputs include 1a, 1b, 1c; 2a, 2b, 2c; and 3a, 3b, 3c for metering and protection applications. The built-in fuse provides integrated overcurrent protection in the primary circuit. Ensure correct polarity and phase sequence during installation.
Selection & FAQs
Selection Guide
- Choose the right model: Select JDZW-35R/280 for standard voltage measurement with 1000VA thermal limit output, or JDZX(F)W-35R if ground fault detection is required.
- Select appropriate accuracy class: Use class 0.2 for revenue metering, 0.5 for monitoring, 1.0 for general measurement, and 3P or 6P for protection applications.
- Match burden requirements: Ensure the rated output aligns with connected devices (meters, relays); JDZW-35R/280 offers 1000VA while JDZX(F)W-35R provides 600VA thermal limit output.
- Verify environmental suitability: Confirm ambient temperature (-25°C to +40°C) and altitude (≤1000m standard) match your installation site.
- Consider space and maintenance needs: The compact, epoxy cast-resin design is ideal for tight spaces and requires no maintenance.
- Leverage integrated protection: Built-in fuse eliminates need for external overcurrent protection components.
Frequently Asked Questions
Q1: Can this 35kV voltage transformer be installed at high altitudes?
Yes, standard models support altitudes up to 1000m. For installations above 1000m, customized high-altitude designs are available upon request. Contact our engineering team for specific altitude requirements.
Q2: Which accuracy class is suitable for protective relaying applications?
The 1.0 accuracy class with 200VA rated output is recommended for protection circuits. It ensures reliable performance under fault conditions while supporting up to 1000VA maximum output.
Q3: How does the built-in fuse protect against secondary short circuits?
The integrated fuse provides immediate overcurrent protection for the secondary winding. This prevents thermal damage during fault conditions without requiring external protective devices.
Q4: Can a single JDZW-35R unit measure a three-phase 35kV system?
No, this is a single-phase epoxy cast-resin transformer. You must install three separate units to form a complete three-phase measurement bank for 35kV outdoor substations.
Q5: What international standards does this outdoor voltage transformer comply with?
The JDZW-35R series complies with GB20840.1-2010 and GB20840.3-2013 standards. For IEC or IEEE compliance certificates, please contact our sales department for project-specific documentation.
Q6: Are these 35kV transformers compatible with 60Hz power grids?
Yes, the design supports both 50Hz and 60Hz operating frequencies. Specify your exact grid frequency and rated voltage requirements during the inquiry stage for factory confirmation.
Q7: Why choose epoxy cast-resin insulation for outdoor substations?
Epoxy resin offers maintenance-free operation and eliminates the need for periodic oil testing. It provides reliable 40.5/95/200kV insulation levels in harsh outdoor environments.