Overview
The JLSW3-33 is an outdoor horizontal oil-immersed high-voltage metering tank rated for 33kV systems (suitable for 35kV-class applications). It integrates both voltage and current transformers within a single sealed, oil-filled tank, utilizing oil as the primary insulation and cooling medium for reliable outdoor operation.
This metering device supports high-accuracy classes such as 0.2S and 0.5S, meeting utility-grade requirements for energy settlement and power monitoring. It is commonly deployed in rural distribution networks, industrial substations, pole-mounted installations, and utility metering points, complying with relevant IEC and national standards for high-voltage instrument transformers.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| Rated system voltage | 33kV (for 35kV-class systems) |
| Primary voltage (VT) | 33,000 / √3 V |
| Secondary voltage (VT) | 100 / √3 V or 100 V |
| Primary current (CT) | As per order (e.g., 100–600 A) |
| Secondary current (CT) | 5 A or 1 A |
| Voltage transformer accuracy | 0.2, 0.5 (metering class) |
| Current transformer accuracy | 0.2S, 0.5S (metering class) |
| Insulation medium | Transformer oil |
| Installation type | Outdoor, horizontal |
| Phase configuration | Three-phase three-wire or four-wire |
| Bushing type | Porcelain, outdoor-rated |
| Protection | Oil-sealed, tamper-resistant options available |
Model Designation
- J: Voltage transformer / metering transformer category
- L: Current transformer component
- S: Three-phase system
- W: Outdoor device / horizontal outdoor structure
- 3: Design sequence number
- 33: Rated voltage class: 33kV
Construction
The JLSW3-33 features a robust, low-profile horizontal tank constructed from welded steel plates, fully sealed and filled with insulating transformer oil. The internal core-and-coil assemblies for both voltage and current transformers are immersed in oil, which provides dielectric insulation and thermal stability under continuous outdoor operation. High-voltage porcelain bushings are mounted on both sides of the tank for primary line connections, ensuring adequate creepage distance and weather resistance. The tank includes an oil expansion chamber, oil-level indicator, and grounding terminals compliant with outdoor service requirements. All external hardware and sealing gaskets are selected for UV resistance, temperature cycling, and long-term environmental durability.
Technical Parameters
Service Conditions
- Installation location: outdoor
- Applicable system: 33kV / 35kV-class AC power system
- Rated frequency: 50Hz / 60Hz
- Electrical clearance and grounding: The product should be installed in an outdoor location with sufficient electrical clearance and grounding conditions.
- Mechanical support: The installation foundation, pole frame, or platform should support the tank weight and mechanical stress from connected conductors.
- Lightning protection: Surge arrester or lightning protection device should be installed according to project design and local power system requirements.
- Special environments: For high altitude, heavy pollution, coastal environment, low-temperature area, or special seismic requirements, technical confirmation is recommended before ordering.
Technical Parameters
The JLSW3-33 is an outdoor horizontal oil-immersed high-voltage metering tank designed for 33kV (35kV-class) systems. It features oil-immersed insulation, operates at 50Hz or 60Hz, and supports rated currents from 5A to 300A. The unit complies with GB/T 20840 series standards and is suitable for standard outdoor service conditions unless specified otherwise for extreme environments.
General Technical Data
| Item | Specification |
|---|---|
| Rated voltage | 33kV, suitable for 35kV-class systems |
| Highest voltage for equipment | 40.5kV, subject to project specification |
| Rated frequency | 50Hz / 60Hz |
| Current Range | 5A to 300A, or customized according to project requirement |
| Accuracy Class | 0.2S, 0.5S, 0.5, 1.0 according to metering requirement |
| Insulating medium | Transformer oil |
| Structure | Outdoor horizontal combined transformer tank |
| Transformer components | Current transformer units and voltage transformer units |
| Installation method | Outdoor pole-mounted, frame-mounted, or platform-mounted installation |
| Applicable standards | GB/T 20840.1, GB/T 20840.2, GB/T 20840.3, GB/T 20840.4; project-specific requirements can be confirmed by agreement |
Metering Accuracy and Electrical Parameter Reference
| Parameter | Reference Value | Remark |
|---|---|---|
| Rated voltage class | 33kV | For 35kV-class outdoor metering systems |
| Highest system voltage | 40.5kV | Subject to final technical agreement |
| Rated Primary Current | 5A–300A | Custom ratio available according to line current |
| Accuracy Class | 0.2S / 0.5S / 0.5 / 1.0 | Selected according to metering or settlement requirement |
| Rated frequency | 50Hz / 60Hz | According to project power system |
| Insulating medium | Transformer oil | Oil-immersed insulation and heat dissipation |
Installation & Wiring
Installation Diagram
The JLSW3-33 is designed for outdoor horizontal installation on pole-mounted frames, brackets, or platforms. The tank body is mounted horizontally with high-voltage porcelain bushings positioned on both sides for three-phase incoming and outgoing line connections. Ensure stable mechanical support, adequate electrical clearance, and accessibility for oil-level inspection and grounding.
Selection & FAQs
Selection Guide
- Confirm the 33kV nominal system, 40.5kV equipment class, frequency, phase wiring, and utility metering scheme.
- Specify the VT ratio and secondary voltage, then select the 5A–300A CT ratio and secondary output.
- Choose the required accuracy class and calculate the burden for each CT and VT secondary circuit.
- Define outdoor pollution, altitude, coastal, temperature, seismic, sealing, and surge-protection requirements.
- Verify horizontal support, bushing loads, line clearances, grounding, oil access, lifting, and certified dimensions.
Frequently Asked Questions
Q1: What is the JLSW3-33 high-voltage metering tank used for?
It is designed for 33kV and 35kV-class outdoor AC power systems. The unit provides accurate energy metering and measurement for substations. Contact us for specific substation integration details.
Q2: Can this 33kV metering tank operate on 60Hz power systems?
Yes, it supports both 50Hz and 60Hz rated frequencies. Ensure your system frequency matches the nameplate specification before installation. Factory confirmation is recommended for dual-frequency requirements.
Q3: How to install the tank in heavy pollution or coastal areas?
Standard models are for normal outdoor conditions. For heavy pollution or coastal environments, technical confirmation is required before ordering. We will provide customized insulation and protection solutions.
Q4: Which international standards does this oil-immersed metering tank comply with?
The JLSW3-33 complies with the GB/T 20840 series standards. If you require specific IEC or IEEE certifications for your project, please contact our sales team for details.
Q5: What are the rated current options for this metering tank?
It supports rated currents ranging from 5A to 300A. Select the appropriate primary current rating based on your maximum load requirements. Specify the exact current ratio during procurement.
Q6: Are special seismic or high-altitude configurations available for this model?
Custom configurations for high altitude or special seismic requirements are available. These modifications are subject to technical confirmation based on your exact site parameters. Please provide project specifications for a tailored quote.
Q7: Does the tank include built-in lightning protection devices?
No, built-in surge arresters are not included. A separate lightning protection device must be installed according to your project design and local power system requirements. Consult your electrical engineer for proper grounding.