Overview
The JDZW-35 JDZFW-35, JDZXFW-35 (JDZW-35QIV) is a fully-enclosed, single-phase outdoor voltage transformer rated for 35 kV systems. It features epoxy resin cast insulation, providing robust dielectric strength, moisture resistance, and long-term stability in harsh outdoor environments.
Designed for high accuracy in metering (classes 0.2, 0.5) and protection (e.g., 6P), it supports applications including revenue metering, relay protection, and SCADA integration in 35 kV substations and distribution networks. The unit complies with IEC 61869-3/-1 and GB/T 20840.3/20840.1 standards, ensuring reliable performance under standard operating conditions at 50 Hz (60 Hz optional).
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System voltage class | 35 kV (outdoor) |
| Rated frequency | 50 Hz (60 Hz on request) |
| Rated secondary voltage | 100 V or 100/√3 V |
| Accuracy classes | 0.2, 0.5 (metering); 6P (protection) |
| Rated burden | As specified per core (VA) |
| Burden power factor | cosφ = 0.8 lagging |
| Insulation level | 40.5/95/200 kV (Um/LIPL/ACSD) |
| Applicable standards | IEC 61869-3, IEC 61869-1, GB/T 20840.3, GB/T 20840.1 |
Model Designation
- J: Voltage transformer (VT / PT)
- D: Single-phase design
- Z: Support (pillar / post) type
- W: Outdoor installation
- 35: Voltage class (kV)
- F: Fuse-equipped variant
- X: Auxiliary secondary winding for open-delta connection
Construction
The transformer employs a pillar-type (post-type) structure optimized for outdoor mounting, featuring fully enclosed epoxy resin cast insulation formulated for UV resistance and anti-tracking performance. The magnetic core consists of cold-rolled grain-oriented silicon steel laminations, heat-treated to enhance magnetic characteristics. Advanced vacuum casting technology ensures void-free insulation with uniform dielectric properties. A sealed metal terminal box with padlock provision houses all secondary terminals, offering protection against environmental ingress and unauthorized access. This compact, maintenance-free design delivers excellent pollution performance, weather resistance, and long-term reliability in outdoor service conditions.
Technical Parameters
Service Conditions
- Installation environment: Outdoor installation
- Altitude: Not exceeding 1000 m above sea level (higher altitude shall be specified for engineering confirmation)
- Ambient temperature: −5 °C to +40 °C
- Relative humidity: Daily average ≤ 95%, monthly average ≤ 90% (at +20 °C reference)
- Environmental conditions: Free from corrosive gases or vapors; free from explosive or flammable media; pollution severity level II per IEC 60815
Technical Parameters
The JDZW-35 series is a fully-enclosed cast-resin outdoor voltage transformer designed for 35 kV class AC systems operating at 50 Hz. It features an insulation level of 40.5/95/200 kV, complies with IEC 61869-1 standards, and is rated for ambient temperatures from −5 °C to +40 °C and altitudes up to 1000 m.
Voltage Transformer Data
| Model | Type (Ratio) |
Accuracy Class (Protection/ Measurement) |
Rated Output (VA) |
Maximum Output (VA) |
Rated Insulation Level (kV) |
|---|---|---|---|---|---|
| JDZW-35 | 35000/100 | 0.2 | 75 | 1000 | 40.5/95/200 |
| JDZW-35 | 35000/100 | 0.5 | 100 | 1000 | 40.5/95/200 |
| JDZFW-35 | 35000/100/100 | 0.2/0.2 | 30/30 | 2 × 500 | 40.5/95/200 |
| JDZFW-35 | 35000/100/100 | 0.2/0.5 | 30/60 | 2 × 500 | 40.5/95/200 |
| JDZFW-35 | 35000/100/100 | 0.5/0.5 | 60/60 | 2 × 500 | 40.5/95/200 |
| JDZXW-35 | 35000/√3 / 100/√3 / 100/3 | 0.2/6P | 40/100 | 1000 | 40.5/95/200 |
| JDZXW-35 | 35000/√3 / 100/√3 / 100/3 | 0.5/6P | 80/100 | 1000 | 40.5/95/200 |
| JDZXW-35 | 35000/√3 / 100/√3 / 100/3 | 0.2/0.2/6P | 20/20/100 | 1000 | 40.5/95/200 |
| JDZXFW-35 | 35000/√3 / 100/√3 / 100/3 / 100/3 | 0.2/0.5/6P | 25/25/100 | 2 × 400 | 40.5/95/200 |
| JDZXFW-35 | 35000/√3 / 100/√3 / 100/3 / 100/3 | 0.5/0.5/6P | 40/40/100 | 2 × 400 | 40.5/95/200 |
Installation & Wiring
Outline Dimensions
The outline drawing provides critical dimensional data including overall height, width, depth, and location of mounting holes. These dimensions must be referenced to ensure proper fitment on the designated foundation or support structure.
Wiring Diagram
The wiring diagram illustrates terminal markings and connection arrangements for primary and secondary windings. Primary terminals are typically labeled A and X, while secondary terminals follow standard voltage transformer designation (e.g., a, x or da, dx for auxiliary windings if present). Connections must be made in strict accordance with the diagram to ensure correct polarity and metering/protection performance.
Selection & FAQs
Selection Guide
- Select the correct model variant (JDZW-35, JDZFW-35, JDZXW-35, or JDZXFW-35) based on whether metering, protection, or residual voltage detection is required.
- Specify the voltage ratio to match the system nominal voltage (35 kV) and secondary instrument requirements (typically 100 V or 100/√3 V).
- Define accuracy classes for each secondary core—e.g., Class 0.2 for revenue metering, Class 0.5 for indication, and Class 6P for protection—per IEC 61869 and GB/T 20840 standards.
- Calculate and specify the rated burden (VA) for each winding to account for connected instruments and wiring losses at 100 V secondary voltage.
- Confirm insulation level (standard: 40.5/95/200 kV) meets system requirements based on network configuration and grounding method.
- For ground fault detection in ungrounded or resistance-grounded systems, choose JDZXW-35 or JDZXFW-35 variants with an auxiliary winding (da/dn terminals).
Frequently Asked Questions
Q1: Are these 35kV outdoor voltage transformers suitable for high-altitude installations?
Standard models are rated for altitudes up to 1000 meters above sea level. For higher elevations, please specify the exact altitude for engineering confirmation and potential design adjustments.
Q2: Which accuracy class should I select for measurement applications?
Select the 0.2 class for precise measurement requiring 75 VA rated output, or the 0.5 class for standard applications needing 100 VA. Both operate with a 35000/100 V ratio.
Q3: What is the rated insulation level for the JDZW-35 series?
The JDZW-35 series features a rated insulation level of 40.5/95/200 kV. It is fully enclosed in cast-resin and complies with IEC 61869-1 standards for 35 kV AC systems.
Q4: Do you provide factory testing and calibration certificates before shipment?
Yes, standard routine tests are performed prior to dispatch to ensure compliance with IEC 61869-1. Contact our sales team for specific calibration certificate requirements or special test reports.
Q5: Can the ambient temperature range be customized for extreme climates?
The standard operating temperature range is −5 °C to +40 °C. For projects requiring operation outside these limits, please provide your specific environmental conditions for factory evaluation.
Q6: Where is the JDZFW-35 voltage transformer typically applied?
This cast-resin outdoor voltage transformer is designed for 35 kV class, 50 Hz AC power systems. It is typically applied in outdoor switchgear and substations for voltage measurement.
Q7: How does this transformer handle severe outdoor pollution conditions?
The housing is designed to withstand pollution severity level II per IEC 60815 standards. Ensure the installation environment remains free from corrosive gases and explosive media.