Overview
The JLSZV-35 is an indoor epoxy resin cast three-phase two-component combined transformer rated for 35kV systems with 40.5kV class insulation. It integrates both current transformer (CT) and voltage transformer (PT) functions into a single epoxy cast-resin assembly, delivering precise current and voltage signals for metering and protection.
Designed for high-accuracy applications, it supports accuracy classes up to 0.2S for revenue metering and complies with GB20840.4-2015 and IEC 61869.4 standards. The unit is ideal for indoor switchgear, compact substations, and industrial facilities with 35kV incoming supply where space efficiency and long-term reliability are critical.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System Voltage | 35kV |
| Insulation Level | 40.5kV |
| Frequency | 50Hz |
| Current Ratio Range | 5A – 1200A |
| Voltage Ratio | 35kV/√3 : 100V/√3 |
| Metering Accuracy (CT) | 0.2S / 0.2 |
| Protection Accuracy (CT) | 5P10 / 5P20 |
| PT Accuracy Class | 0.2 / 0.5 |
| Thermal Stability | 4s short-time withstand current |
| Ambient Temperature Range | -25°C to +55°C |
| Indoor Use Only | Yes |
| Insulation Material | Epoxy cast-resin |
Model Designation
- J: Combined instrument transformer (CT + PT)
- L: Current transformer component
- S: Three-phase structure
- Z: Cast-resin insulated
- V: Voltage transformer component included
- 35: Rated system voltage of 35kV
Construction
The JLSZV-35 features a monolithic epoxy cast-resin construction that encapsulates both the current and voltage transformer cores and windings in a single solid housing. This design provides excellent dielectric strength, moisture resistance, and mechanical stability without requiring oil or gas insulation. Primary conductors are embedded within the resin matrix, while secondary windings are led out through a sealed terminal box mounted on the base. The absence of moving parts and the use of thermoset epoxy ensure maintenance-free operation and long service life in controlled indoor environments. All external surfaces are smooth and non-hygroscopic, preventing surface tracking and ensuring consistent performance under normal indoor operating conditions.
Technical Parameters
Service Conditions
- Installation position: Indoor switchgear, metering cabinets, or compact substations
- Ambient temperature: -25°C to +55°C
- Maximum altitude: ≤ 4500m (no derating required)
- Environment: Indoor with controlled temperature and humidity
- Grounding: Connect grounding terminal per local electrical codes and metering standards
- Maintenance: Epoxy resin construction requires minimal maintenance in indoor environments
Technical Parameters
The JLSZV-35 is an indoor epoxy cast-resin combined transformer for 35kV systems featuring a three-phase two-component design. It has 40.5kV class insulation, operates within -25°C to +55°C ambient temperature, supports altitudes up to 4500m without derating, complies with GB20840.4-2015 and IEC 61869.4:2013, and offers a wide primary current range from 5A to 1200A.
Voltage Transformer Data
| Rated Voltage Ratio (kV) |
Rated Insulation Level (kV) |
Accuracy Class / Rated Output |
Max Output (VA) |
|---|---|---|---|
| 35/0.1 | 40.5/95/200 | 0.2 (2×30VA), 0.5 (2×60VA) | 600 |
| 33/0.1 | 40.5/95/200 | 0.2 (2×30VA), 0.5 (2×60VA) | 600 |
Current Transformer Data
| Rated Primary Current (A) |
Rated Insulation Level (kV) |
Accuracy Class / Rated Output |
Short-Time Thermal Current |
Dynamic Current |
|---|---|---|---|---|
| 5 – 600 | 40.5/95/185 | 0.2S (2×15VA) | 80 × In | 200 × In |
| 750 – 800 | 40.5/95/185 | 0.2S (2×15VA) | 80 kA | 200 kA |
| 1000 – 1200 | 40.5/95/185 | 0.2S (2×20VA) | 100 kA | 250 kA |
Installation & Wiring
Installation Diagram
The JLSZV-35 Indoor Epoxy Resin Combined Transformer is designed for secure indoor mounting on a flat, load-bearing surface. Installation requires alignment with the mounting base as shown in the end view (width 840mm), ensuring adequate clearance around the unit for ventilation and access to terminals. The four bushings with terminals are positioned on the side, while the top view shows the terminal layout (AP1, AP2, CP1, CP2) for proper connection sequencing.
Wiring Diagram
The wiring diagram illustrates connections for both current transformer (CT) and voltage transformer (PT) circuits within the combined unit. Terminals AP1 and AP2 correspond to the primary voltage input, while CP1 and CP2 are associated with the current measurement path. CT secondary terminals supply current signals to energy meters and protection devices, and PT secondary terminals provide voltage inputs to meters and relays. All grounding and interconnections must strictly follow the approved project wiring diagram to ensure safety and accuracy.
Selection & FAQs
Selection Guide
- Select JLSZV-35 for 35kV systems with 40.5kV class insulation.
- Choose CT primary current between 5A and 1200A based on actual load, available in three segments: 5–600A, 750–800A, and 1000–1200A.
- Specify CT accuracy class as 0.2S for high-accuracy energy metering applications.
- Select PT voltage ratio as either 35/0.1kV or 33/0.1kV to match network voltage and meter input requirements.
- Confirm indoor installation environment, as this model is not suitable for outdoor use.
Frequently Asked Questions
Q1: Can this 35kV combined transformer be installed at high altitudes?
Yes, it supports altitudes up to 4500m without derating. It is designed for indoor environments with controlled temperature and humidity between -25°C and +55°C.
Q2: Which accuracy class is available for the voltage transformer?
The unit offers 0.2 and 0.5 accuracy classes. Rated outputs are 2×30VA for class 0.2 and 2×60VA for class 0.5, with a 600VA maximum output.
Q3: What is the primary current range for this combined transformer?
The current transformer supports a primary current range from 5A to 1200A. It features a three-phase, two-component design for 35kV indoor systems. Contact us to specify exact current ratios.
Q4: Does this 35kV transformer comply with specific international standards?
It complies with GB20840.4-2015 and IEC 61869.4:2013 standards. The 40.5kV class insulation ensures reliable performance in indoor switchgear and metering cabinets.
Q5: How much maintenance is required for the epoxy resin construction?
Epoxy resin construction requires minimal maintenance in indoor environments. Ensure proper grounding terminal connection per local electrical codes during installation.
Q6: Where can the JLSZV-35 combined transformer be applied?
It is ideal for indoor switchgear, metering cabinets, and compact substations. The 35/0.1kV and 33/0.1kV voltage ratios serve 35kV and 33kV networks. Contact sales for project pricing.