Overview
The JDZ11-10A/185 / UNZ10 is an indoor single-phase epoxy cast-resin voltage transformer designed for 6kV, 10kV, 11kV and 12kV class medium-voltage systems. It features a fully enclosed vacuum cast-resin insulation structure, providing high dielectric strength, moisture resistance, and mechanical durability for indoor switchgear applications.
This transformer supports accuracy classes of 0.2 and 0.5 for metering, and 3P or 6P for protection or residual-voltage functions. It is suitable for voltage measurement, energy metering, relay protection, and automatic control signal conversion in 50Hz or 60Hz power systems, complying with standard IEC and national requirements for indoor voltage transformers.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| Voltage class | 6kV, 10kV, 11kV, 12kV |
| Rated frequency | 50Hz / 60Hz |
| Insulation level (10kV class) | 12/42/75kV |
| Insulation level (6kV class) | 7.2/32/60kV |
| Primary voltage ratio | 6/√3, 10/√3, 11/√3 kV |
| Secondary voltage ratio | 0.1/√3, 0.11/√3, 0.1/3 kV |
| Metering accuracy | 0.2, 0.5 |
| Protection accuracy | 3P, 6P |
| Maximum output | 350VA |
| Phase configuration | Single-phase |
| Insulation type | Epoxy cast-resin |
| Application | Indoor switchgear, metering, protection |
Model Designation
- J: Voltage transformer / potential transformer
- D: Single-phase structure
- Z: Epoxy resin cast insulation
- X: Phase-to-earth or residual-voltage function (in JDZX variants)
- 11: Design sequence code for fully enclosed cast-resin structure
- 10A: 10kV class model reference and structural variant
- 185: Cast-resin body width dimension in millimetres
Construction
The JDZ11-10A/185 / UNZ10 features a robust, fully enclosed epoxy vacuum cast-resin construction. All primary and secondary windings are completely encapsulated in high-quality epoxy resin under vacuum conditions, ensuring uniform insulation, excellent partial discharge performance, and long-term reliability. The solid cast body provides superior resistance to humidity, dust, and mechanical stress, making it ideal for indoor medium-voltage environments. Primary terminals (A, N) and secondary terminals (a, n) are clearly marked on the resin surface for easy identification and wiring. The compact 185mm body width allows for efficient use of space in switchgear cabinets and facilitates direct replacement in retrofit projects.
Technical Parameters
Service Conditions
- Ambient temperature: -25°C to +40°C
Technical Parameters
The JDZ11-10A/185 / UNZ10 is an indoor fully enclosed epoxy cast-resin voltage transformer designed for 6kV, 10kV, 11kV, and 12kV class systems. It features vacuum-cast epoxy resin insulation, operates within a temperature range of -25°C to +40°C, complies with IEC 61869-3, IEC 61869-1, GB/T 20840.3-2013, and other relevant standards, and supports rated outputs up to 350VA.
| Model | Rated Voltage Ratio |
Rated Insulation Level (kV) |
Accuracy Class Rated Output (VA) |
Maximum Output (VA) |
|---|---|---|---|---|
| JDZX11-10/185 | 6/√3 : 0.1/√3 : 0.1/3 6.3/√3 : 0.1/√3 : 0.1/3 |
7.2 / 32 / 60kV | 0.2 / 3P: 15 / 60VA 0.2 / 6P: 15 / 60VA 0.5 / 3P: 30 / 60VA 0.5 / 6P: 30 / 60VA |
350VA |
| JDZX11-10/185 UNZ10 |
10/√3 : 0.1/√3 : 0.1/3 11/√3 : 0.11/√3 : 0.1/3 |
12 / 42 / 75kV | 0.2 / 3P: 15 / 60VA 0.2 / 6P: 15 / 60VA 0.5 / 3P: 30 / 60VA 0.5 / 6P: 30 / 60VA |
|
| JDZ11-10A/185 UNZ10 |
10 / 0.1 11 / 0.11 by agreement 12 / 0.11 by agreement |
12 / 42 / 75kV | 0.2: 15VA 0.5: 30VA 1.0: by agreement 3.0: by agreement |
350VA |
Installation & Wiring
Outline Dimensions
The transformer has a casting width of 185 mm and is designed for indoor installation within switchgear. Key dimensional considerations include mounting hole distance, top terminal clearance, secondary terminal direction, and grounding bolt position. Confirm these dimensions prior to production to ensure compatibility with the enclosure and busbar arrangement.
Wiring Diagram
The primary terminal is connected to the high-voltage busbar, while the secondary terminals provide metering or protection outputs as per the specified voltage ratio. Terminal markings follow standard IEC conventions. The wiring method, secondary terminal direction, and grounding connection must be verified against project requirements before installation.
Selection & FAQs
Selection Guide
- Use JDZ11-10A/185 or UNZ10 for compact, fully enclosed single-phase indoor voltage transformers with a 185mm cast-resin body width.
- Select the appropriate voltage class (6kV, 10kV, 11kV, or 12kV) based on system requirements and insulation coordination.
- Choose JDZ for phase-to-phase connections and JDZX for phase-to-earth or residual-voltage applications.
- Specify the correct voltage ratio: 10/√3 : 0.1/√3 : 0.1/3 for phase voltage or 10/0.1 for line voltage measurements.
- Define accuracy class as 0.2 or 0.5 for metering, and 3P or 6P for protection or residual-voltage functions.
Frequently Asked Questions
Q1: Can this 10kV voltage transformer be used on 11kV systems?
Yes, subject to project confirmation. The JDZ11-10A/185 supports 6kV to 12kV class systems with a 12/42/75kV insulation level. Specify your exact system voltage for factory verification.
Q2: Which accuracy class provides the highest measurement precision?
Class 0.2 offers the highest precision for metering. It provides 15VA rated output at 12/42/75kV insulation level. Contact our engineering team to confirm specific burden requirements.
Q3: What are the ambient temperature limits for indoor installation?
The operating ambient temperature range is -25°C to +40°C. This epoxy cast-resin design is strictly for indoor switchgear applications. Ensure adequate ventilation in the installation room.
Q4: Does this voltage transformer comply with international IEC standards?
Yes, it fully complies with IEC 61869-3 and IEC 61869-1 standards. It also meets GB/T 20840.3-2013 requirements. Request the specific type test report during procurement.
Q5: Can the rated voltage ratio be customized for specific projects?
Custom ratios like 11/0.11 or 12/0.11 are available by agreement. Standard ratios include 10/0.1 for typical 10kV applications. Contact sales for customized factory testing details.
Q6: What type of insulation does this indoor transformer use?
It features fully enclosed vacuum-cast epoxy resin insulation. This design ensures high dielectric strength for 12kV indoor switchgear. Ideal for compact indoor substations.
Q7: What is the maximum thermal output capacity for this model?
The maximum output capacity is 350VA. Standard accuracy classes range from 0.2 to 3.0 with rated outputs between 15VA and 60VA. Verify your connected burden before ordering.