Overview
The JDZX9-35D/290 is an indoor single-phase epoxy resin cast voltage transformer rated for 35kV medium-voltage systems. It utilizes cast-resin insulation technology with an arch-type structural design, ensuring high dielectric strength and maintenance-free operation in controlled indoor environments.
This transformer supports multiple accuracy classes (0.2, 0.5, 3P) and includes a residual voltage winding for ground fault detection. It is suitable for energy metering, voltage monitoring, and relay protection applications in 35kV indoor distribution networks, meeting standard requirements for insulation levels of 40.5/95/200kV and delivering up to 800VA output capacity.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System Voltage | 35kV |
| Insulation Level | 40.5/95/200kV |
| Primary Voltage | 35/√3 kV |
| Secondary Voltage (Main) | 100/√3 V |
| Secondary Voltage (Residual) | 100 V |
| Accuracy Classes | 0.2, 0.5, 3P |
| Maximum Output | 800VA |
| Frequency | 50Hz |
| Phase | Single-phase |
| Installation Type | Indoor |
| Insulation Material | Epoxy resin cast |
| Weight | 77kg |
Construction
The JDZX9-35D/290 features a robust epoxy resin cast construction, providing excellent electrical insulation, moisture resistance, and mechanical stability. The core and windings are fully encapsulated in self-extinguishing epoxy resin under vacuum conditions, eliminating air voids and enhancing partial discharge performance. The arch-type housing design improves structural rigidity while minimizing material usage and weight. All primary and secondary terminals are embedded within the cast body, offering protected connection points compliant with indoor safety standards. This sealed, maintenance-free construction ensures long-term reliability in clean, dry indoor switchgear and substation environments without exposure to UV radiation or weathering.
Technical Parameters
Service Conditions
- Installation position: Indoor switchgear, substations, or distribution points
- Ambient temperature: -25°C to +40°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 JDZX9-35D/290 is an indoor epoxy resin cast single-phase voltage transformer designed for 35kV systems. It operates within a temperature range of -25°C to +40°C and at altitudes up to 1000m (higher on request). The unit complies with GB20840.3-2013 and IEC61869-3:2011 standards and supports multiple secondary winding configurations with outputs up to 800 VA.
| Type | Rated ratio(V) | Accuracy class /
Rated output (VA) |
Max.
output (VA) |
Rated
insulation (kV) |
|---|---|---|---|---|
| JDZX9-35D/290 | 35/√3 : 0.1/√3 : 0.1/3 | 0.2/3P-75/100 0.5/3P-200/100 |
800 | 40.5/95/200 |
| 35/√3 : 0.1/√3 : 0.1/√3 : 0.1/3 | 0.2/0.5/3P-50/60/100 | 800 | ||
| 35/√3 : 0.1/√3 : 0.1/√3 : 0.1/√3 : 0.1/3 | 0.2/0.5/3/3P-50/50/100/100 | 600 |
Installation & Wiring
Installation Diagram
The JDZX9-35D/290 is designed for secure indoor mounting using four bolts through the base mounting holes spaced at 300mm x 320mm. The unit’s arch-type structure with a hollow center allows for reduced weight (approximately 77kg) while maintaining mechanical stability and heat dissipation.
Wiring Diagram
Primary windings are connected in star configuration with the neutral point grounded. Secondary windings for measurement and protection are also wired in star configuration. A dedicated residual voltage winding is provided and must be connected in open-delta configuration to enable zero-sequence voltage detection for ground fault monitoring. All secondary circuits must be properly grounded, and terminal markings should be verified against system requirements before commissioning.
Selection & FAQs
Selection Guide
- Select for 35kV system voltage with 40.5/95/200kV insulation level.
- Choose winding configuration: two-winding for basic use, three-winding for added flexibility, or four-winding for maximum versatility.
- Pick accuracy class based on application: 0.2 for high-precision metering, 0.5 for standard metering, or 3P for protection.
- Specify rated output between 50–200VA according to connected burden requirements.
- Confirm frequency (50Hz or 60Hz) and indoor installation type during ordering.
Frequently Asked Questions
Q1: Can this cast-resin voltage transformer be installed outdoors?
No, it is strictly designed for indoor installation in switchgear or substations. The epoxy resin insulation is optimized for indoor environmental conditions up to 40°C. Contact us for outdoor-rated alternatives.
Q2: Which accuracy class is available for protection relays?
The 3P accuracy class is available for protection applications, offering 100 VA rated output. It ensures reliable operation during fault conditions per IEC61869-3 standards. Specify your exact burden during ordering.
Q3: How many units are needed for a three-phase system?
Three single-phase units are required to form a complete three-phase system. Each JDZX9-35D/290 unit operates independently and connects in the standard three-phase configuration. Confirm the primary ratio requirements for your specific setup.
Q4: Can the altitude rating exceed the standard 1000m limit?
Yes, higher altitude versions are available upon request. Standard units are rated for altitudes up to 1000m, but custom designs can accommodate elevated installations. Provide your exact site altitude for factory evaluation.
Q5: What international standards does this 35kV transformer comply with?
It complies with both GB20840.3-2013 and IEC61869-3:2011 standards. These ensure global compatibility for 35kV indoor voltage measurement applications. Request specific type test reports for your project documentation.
Q6: What is the maximum output capacity for this model?
The JDZX9-35D/290 supports a maximum output of 800 VA. This high capacity makes it suitable for heavy-burden indoor substation metering and protection panels. Verify your total connected burden with our engineering team.
Q7: Why use epoxy resin cast insulation for 35kV systems?
Epoxy resin provides excellent dielectric strength and requires minimal maintenance. It features rated insulation levels of 40.5/95/200 kV. Contact our sales team for detailed dielectric test certificates.