Overview
The JDZX12-35R is a single-phase indoor voltage transformer rated for 35kV medium-voltage systems. It features epoxy cast-resin insulation, ensuring high dielectric strength, moisture resistance, and maintenance-free operation in indoor environments.
Designed for energy metering, voltage monitoring, and relay protection, it offers accuracy classes of 0.2, 0.5, 1.0, and 6P. Available in three-winding (Y/△) or four-winding (Y/Y/△) configurations, it supports ground fault detection via an open-delta residual winding. With a thermal limit output of up to 600VA, it complies with standard requirements for indoor 35kV distribution applications.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System Voltage | 35kV |
| Maximum System Voltage | 40.5kV |
| Primary Voltage | 35/√3 kV |
| Secondary Voltage | 100/√3 V or 100 V |
| Residual Voltage | 100 V (open-delta) |
| Accuracy Classes | 0.2, 0.5, 1.0, 6P |
| Thermal Limit Output | 600 VA |
| Insulation Level | 40.5/95/200 kV (Um/LI/AC) |
| Phase | Single-phase |
| Installation Type | Indoor |
| Insulation Material | Epoxy cast-resin |
| Weight | 68 kg |
Construction
The JDZX12-35R features a robust epoxy cast-resin construction, encapsulating all active components in a solid, void-free insulation system. This design provides excellent mechanical strength, superior partial discharge resistance, and long-term stability under electrical stress. The core and windings are fully embedded in flame-retardant epoxy resin, ensuring high tracking resistance and moisture immunity. Terminal connections are integrated into the cast body with clearly marked polarity indicators. The compact, sealed structure eliminates the need for oil or gas insulation, making it suitable for clean, maintenance-free operation in indoor switchgear and substations.
Technical Parameters
Service Conditions
- Installation position: Indoor switchgear, substations, or distribution points
- Ambient temperature: -5°C to +50°C
- Altitude: ≤ 1000m (standard), higher altitude available on request
- Insulation: Epoxy resin cast
- Frequency: 50Hz or 60Hz
- Connection: Single-phase (three units for three-phase system)
- Maintenance: Minimal maintenance required (epoxy resin design)
Technical Parameters
The JDZX12-35R series comprises indoor epoxy cast-resin single-phase voltage transformers rated for 35kV systems. Designed for operation in ambient temperatures from -5°C to +50°C and standard altitudes up to 1000m, these units comply with GB20840.3-2013 and IEC60044-2:2003 standards.
| Type | Rated ratio(V) | Accuracy
classes |
Rated
Output(VA) |
Thermal limit
output(VA) |
|---|---|---|---|---|
| JDZXW12-35R | 33/√3 : 0.11/√3 35/√3 : 0.1/√3 : 0.1/√3 |
0.2/6P(3P) | 45/100 | 600 |
| 0.5/6P(3P) | 100/100 | |||
| 1.0/6P(3P) | 200/100 | |||
| 35/√3 : 0.1/√3 : 0.1/√3 : 0.1/3 | 0.2/0.2/6P(3P) | 20:20/100 | 600 corresponding to 0.2 class |
|
| 0.2/0.5/6P(3P) | 20:30/100 | |||
| 0.5/0.5/6P(3P) | 40:40/100 |
Installation & Wiring
Outline Dimensions
Overall dimensions: 815±10mm (height) × 403mm (width) × 280mm (depth). Weight: approximately 68kg. Mounting holes: 4×M6 on base plate.
Wiring Diagram
Figure 1: Y/△ Connection (Three-Winding) – Primary terminals A, B, C connect to star configuration, secondary outputs a, b, c for metering, da/dn for open-delta ground fault detection.
Figure 2: Y/Y/△ Connection (Four-Winding) – Enhanced configuration with dual secondary winding sets (1a/1b/1c and 2a/2b/2c) plus delta output (da/dn) for maximum flexibility.
Selection & FAQs
Selection Guide
- Accuracy Class: Select class 0.2 for revenue metering, 0.5 for monitoring, 1.0 for general measurement, or 6P/3P for protection applications.
- Winding Configuration: Choose three-winding (Y/△) for basic metering and protection, or four-winding (Y/Y/△) for dual secondary outputs and added redundancy.
- Burden Matching: Ensure the rated output (e.g., 45/100VA) aligns with the total load of connected devices to maintain specified accuracy.
- Environmental Suitability: Confirm installation conditions fall within standard limits: ambient temperature -5°C to +50°C and altitude ≤1000m.
- Voltage Ratio: Specify the correct primary-to-secondary ratio (e.g., 35/√3 / 0.1/√3 kV) based on system requirements.
Frequently Asked Questions
Q1: What is the maximum operating altitude for this 35kV voltage transformer?
The standard maximum altitude is 1000m. For higher elevations, custom design is subject to factory confirmation. Contact our engineering team for specific adjustments.
Q2: Which accuracy class is suitable for protective relaying applications?
Select the 6P or 3P accuracy class for protection circuits. These classes ensure reliable performance during fault conditions. Confirm your specific burden requirements with our technical staff.
Q3: How do I configure this single-phase unit for a three-phase system?
You must install three identical single-phase units to form a three-phase bank. This configuration is standard for 35kV indoor switchgear. Verify connection diagrams before installation.
Q4: Which international standards does this epoxy cast-resin PT comply with?
The JDZX12-35R series complies with GB20840.3-2013 and IEC60044-2:2003 standards. Request the specific compliance certificates for your project documentation during the inquiry stage.
Q5: Can this 35kV potential transformer operate on 60Hz power systems?
Yes, it is designed for both 50Hz and 60Hz frequencies. Specify your exact system frequency when placing your order to ensure correct factory calibration.
Q6: Where is the JDZX12-35R indoor voltage transformer typically installed?
It is designed for indoor switchgear, substations, and distribution points. The epoxy resin insulation provides minimal maintenance for indoor 35kV networks.
Q7: How much maintenance is required for this cast-resin design?
Minimal maintenance is required due to the fully enclosed epoxy resin insulation. This design prevents dust and moisture ingress in indoor environments.