Overview
The JLSZY8-10W/340 is a three-phase three-component combined transformer metering box designed for 10kV outdoor medium-voltage distribution systems. It features an epoxy cast-resin insulated assembly integrating both current transformer (CT) and voltage transformer (PT/VT) functions within a robust metal enclosure, ensuring reliable signal output for high-voltage energy metering applications.
This unit delivers accurate active and reactive energy measurement with secondary outputs compatible with standard metering instruments. It is engineered for use in pole-mounted installations, compact substations, and industrial user-side metering points, particularly in environments requiring enhanced insulation performance due to pollution or moisture. The design complies with relevant IEC and GB standards for outdoor high-voltage metering equipment.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System Voltage | 10kV |
| Rated Frequency | 50Hz |
| Primary Current Range | 5A – 300A |
| Secondary Current | 5A |
| Secondary Voltage | 100V / √3 |
| Accuracy Class (CT) | 0.2S / 0.5S |
| Accuracy Class (PT) | 0.2 / 0.5 |
| Insulation Level | 12kV |
| Terminal Spacing | 340mm |
| Enclosure Type | Metal, outdoor-rated |
| Insulation Material | Epoxy cast-resin |
| Application Environment | Outdoor, high-pollution areas |
Construction
The JLSZY8-10W/340 employs a fully enclosed epoxy cast-resin insulation structure for both current and voltage transformers, providing excellent dielectric strength and resistance to environmental stress. The core components are encapsulated in a single monolithic cast-resin body, eliminating air gaps and minimizing partial discharge. This assembly is housed within a grounded metal enclosure that offers mechanical protection and shielding against electromagnetic interference. All primary and secondary terminals are securely embedded in the resin matrix, with secondary wiring routed through a sealed terminal box to prevent moisture ingress. The 340mm spacing between high-voltage terminals enhances creepage distance, making the unit suitable for coastal or industrial areas with high levels of contamination.
Technical Parameters
Service Conditions
- Installation position: Outdoor pole-mounted, outdoor metering box, compact substation or user-side metering point
- Ambient temperature: -15°C to +55°C
- Maximum altitude: ≤ 4500m (no derating required)
- Terminal spacing: 340mm for enhanced creepage distance and insulation performance
- Grounding: Connect grounding terminal per local electrical codes and metering standards
- Maintenance: Inspect primary terminals, secondary terminal box sealing, metal enclosure condition and grounding connection periodically
Technical Parameters
The JLSZY8-10W/340 is a three-phase three-component outdoor epoxy cast-resin combined transformer metering box designed for 10kV systems. It operates within an ambient temperature range of -15°C to +55°C and at altitudes up to 4500m without derating, complying with GB20840.4-2015. The unit supports primary current ratios from 5A to 300A with multiple accuracy classes and burden ratings.
Voltage Transformer Data
| Rated Voltage Ratio |
Accuracy Class | Rated Output (VA) |
Rated Insulation Level (kV) |
|---|---|---|---|
| 10000/√3 / 100/√3 / 100/3V | 0.2 / 0.5 | 40 | 12/40/75 |
Current Transformer Data
| Rated Current Ratio (A) |
Accuracy Class | Rated Output (VA) |
Short-Time Thermal Current |
Dynamic Current |
|---|---|---|---|---|
| 5A to 300A / 5A | 0.2S | 15 | 60 × In | 150 × In |
| 5A to 300A / 5A | 0.2 | 15 | 60 × In | 150 × In |
| 5A to 300A / 5A | 0.5 | 20 | 60 × In | 150 × In |
Installation & Wiring
Installation Diagram
The JLSZY8-10W/340 metering box is designed for wall-mounted or pole-mounted installation. Ensure the mounting surface is level and capable of supporting the 82kg unit. Maintain adequate clearance around the enclosure for ventilation and access during maintenance.
Wiring Diagram
Wiring connections must follow the terminal sequence AP1/AP2, BP1/BP2, and CP1/CP2 as shown in the diagram. The PT secondary terminals supply voltage signals to meters and monitoring equipment, while the CT secondary terminals deliver current signals to active and reactive energy meters. All grounding and internal wiring must conform to the approved project wiring diagram.
Selection & FAQs
Selection Guide
- Select JLSZY8-10W for 10kV systems (12kV insulation class).
- Choose the 340mm terminal spacing version for improved creepage distance in high-pollution or coastal environments.
- Determine CT primary current based on actual load requirements; available range is 5A to 300A with a standard 5A secondary output.
- Specify CT accuracy class as 0.2S for high-accuracy metering, or 0.2/0.5 per local utility or metering standards.
- Select PT voltage ratio as 10/√3 / 0.1/√3 / 0.1/3 kV to match network voltage and meter input specifications.
Frequently Asked Questions
Q1: How is this three-phase combined transformer installed outdoors?
It is designed for outdoor pole-mounted or compact substation installation. The 340mm terminal spacing ensures enhanced creepage distance. Contact our engineering team to verify specific mounting clearances.
Q2: Which accuracy classes are available for the voltage transformer?
The unit offers 0.2 and 0.5 accuracy classes for metering and measurement. It provides a rated output of 40VA with a 10000/√3 / 100/√3 / 100/3V voltage ratio. Contact us to specify your required class.
Q3: Can this 10kV combined transformer operate at high altitudes?
Yes, it operates efficiently at maximum altitudes up to 4500m without requiring any derating. It complies with GB20840.4-2015 standards for ambient temperatures between -15°C and +55°C. Confirm specific site conditions with our engineering team.
Q4: Are custom primary current ratios available for this unit?
Yes, the current transformer section supports ratios ranging from 5A to 300A. Multiple accuracy classes and burden ratings are available to match your project needs. Please provide exact ratio requirements for factory confirmation.
Q5: Which standards does this outdoor metering box comply with?
The JLSZY8-10W/340 fully complies with the GB20840.4-2015 standard. It features a rated insulation level of 12/40/75kV for 10kV systems. Request the specific type test reports and compliance certificates from our sales team.
Q6: What applications are suitable for this three-phase combined transformer?
It is ideal for outdoor metering boxes, compact substations, and user-side metering points in 10kV systems. The epoxy cast-resin enclosure ensures durability in harsh outdoor environments. Contact us for application-specific technical drawings.
Q7: When should routine maintenance be performed on the terminal box?
Routine maintenance requires periodic inspection of the secondary terminal box sealing and metal enclosure. This prevents moisture ingress and ensures grounding connection integrity. Contact us to request the detailed maintenance schedule.