Overview
The JD2-24W and JDX2-24W are outdoor oil-immersed single-phase voltage transformers rated for 24kV systems. They utilize an oil-immersed insulation system that ensures effective thermal dissipation, making them suitable for continuous outdoor operation in demanding environments.
These units support multiple accuracy classes (0.2, 0.5, 3P, 6P) to meet requirements ranging from precision metering to protective relaying. The JD2-24W provides standard voltage transformation, while the JDX2-24W includes a residual voltage winding for ground fault detection. Both comply with GB20840.3-2013 and IEC61869-3:2011 standards and operate reliably between -5°C and +40°C.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System Voltage | 24kV |
| Primary Voltage | 20kV or 20/√3 kV |
| Secondary Voltage | 0.1kV, 0.1/√3 kV, or 0.1/3 kV |
| Thermal Limit Output | 400VA or 800VA |
| Accuracy Classes | 0.2, 0.5, 3P, 6P |
| Insulation Type | Oil-immersed |
| Phase | Single-phase |
| Application | Outdoor |
| Residual Winding | Available on JDX2-24W only |
| Operating Temperature | -5°C to +40°C |
| Standards | GB20840.3-2013, IEC61869-3:2011 |
| Mounting | Concrete foundation |
Construction
The JD2-24W and JDX2-24W feature a robust oil-immersed construction designed for outdoor deployment. The core and windings are fully immersed in insulating oil within a sealed, welded steel tank, which provides both electrical insulation and efficient heat dissipation. The tank includes mounting feet for secure foundation installation and is equipped with high-voltage porcelain bushings rated for 24kV service. All external hardware is corrosion-resistant to withstand prolonged exposure to weather, ensuring long-term reliability in outdoor substations and distribution networks.
Technical Parameters
Service Conditions
- Installation position: Outdoor substations, switching stations, or distribution networks
- Ambient temperature: -5°C to +40°C
- Altitude: ≤ 1000m (standard), higher altitude available on request
- Insulation: Oil-immersed
- Frequency: 50Hz or 60Hz
- Phase configuration: Single-phase (use three units for three-phase systems)
- Maintenance: Periodic oil testing and seal inspection required
Technical Parameters
The JD2-24W/JDX2-24W series are outdoor oil-immersed single-phase voltage transformers designed for 24kV systems. They operate within an ambient temperature range of -5°C to +40°C, up to 1000m altitude, and comply with GB20840.3-2013 and IEC61869-3:2011 standards.
| Type | Rated Voltage | Accuracy Classes
combination |
Rated
output (VA) |
Max.
output (VA) |
|---|---|---|---|---|
| JD(X)W2-20 | 20/0.1 | 0.2 | 40 | 800 |
| 20/0.1/0.1 | 0.5 | 100 | 400 | |
| 0.2/0.2 | 20/20 | |||
| 0.2/0.5 | 20/30 | |||
| 0.5/0.5 | 30/30 | |||
| 20/√3 : 0.1/√3 : 0.1/3 | 0.2/6P(3P) | 20/100 | 600 | |
| 0.5/6P(3P) | 60/100 | |||
| 20/√3 : 0.1/√3 : 0.1/√3 : 0.1/3 | 0.2/0.2/6P(3P) | 15/15/100 | 300 | |
| 0.2/0.5/6P(3P) | 15/20/100 | |||
| 0.5/0.5/6P(3P) | 30/30/100 |
Installation & Wiring
Outline Dimensions
Overall dimensions: Height 752±2mm, Top width 402mm, Base width 310mm, Tank height 345mm. Weight: approximately 84kg. Insulator angle: 19° from vertical. Mounting: Base mounting feet with bolt holes. Maintain a minimum clearance of 600mm around the transformer for maintenance access.
Wiring Diagram
JD2-24W supports single-phase and three-phase connections. Primary terminals A and B connect to the 24kV system. Secondary outputs 1a-1b and 2a-2b are provided for metering and protection circuits. The JDX2-24W model includes an additional residual voltage winding with open-delta connection (da, dn) for ground fault detection. Ensure correct polarity and phase sequence during installation to maintain measurement accuracy and protection reliability.
Selection & FAQs
Selection Guide
- Choose the correct model: Select JD2-24W for standard voltage measurement or JDX2-24W if ground fault detection is needed via its residual voltage winding.
- Select appropriate accuracy class: Use class 0.2 for revenue metering, 0.5 for general monitoring, and 3P/6P for protection applications.
- Match burden requirements: Ensure the rated output (e.g., 40VA, 60VA, 100VA) aligns with the connected load to maintain specified accuracy.
- Confirm environmental suitability: Verify that ambient temperature (-5°C to +40°C) and altitude (≤1000m standard) match your installation site.
- Specify voltage ratio: Choose from standard ratios like 20/0.1kV or 20/√3 : 0.1/√3 : 0.1/3kV based on system configuration and application needs.
Frequently Asked Questions
Q1: Can this 24kV voltage transformer be used for three-phase systems?
Yes, it is a single-phase unit. You must install three identical units to form a three-phase bank for 24kV outdoor substations. Confirm phase configuration during ordering.
Q2: What is the maximum installation altitude for this oil-immersed transformer?
The standard design supports altitudes up to 1000m. For higher elevations, derating or custom design is required. Contact our engineering team for high-altitude specifications.
Q3: Which accuracy classes are available for the secondary windings?
Multiple combinations are available, including 0.2, 0.5, and dual-class options. Rated outputs range from 20VA to 100VA depending on the selected class. Specify your exact metering and protection needs.
Q4: What international standards does this 24kV VT comply with?
It complies with IEC 61869-3:2011 and GB20840.3-2013 standards. Type test reports and certificates of conformity are provided upon request. Verify specific project compliance requirements with our sales team.
Q5: Can this transformer operate on 60Hz power systems?
Yes, it is designed for both 50Hz and 60Hz frequencies. Ensure you specify the exact system frequency and rated voltage when placing your order.
Q6: Where are these outdoor oil-immersed voltage transformers typically applied?
They are primarily used in outdoor substations, switching stations, and 24kV distribution networks. They provide voltage step-down for metering, protection, and control circuits. Request an application guide for more details.
Q7: How should the oil-immersed insulation be maintained in the field?
Periodic oil testing and seal inspections are required to ensure dielectric integrity. Follow standard IEC maintenance guidelines for oil-filled instrument transformers. Contact support for recommended testing intervals.