Overview
The JSZW-10 voltage transformer is an indoor three-phase epoxy cast-resin voltage transformer designed for medium-voltage power systems operating at 50Hz or 60Hz. It supports critical functions including voltage measurement, electric energy metering, voltage monitoring, and relay protection. For international markets, this model is presented as a 10kV, 11kV, and 12kV class indoor cast-resin voltage transformer to align with IEC-oriented project requirements across Southeast Asia, the Middle East, Africa, and other export regions.
This general-purpose indoor VT features a three-phase integrated cast-resin insulated structure, making it ideal for neutral non-effectively grounded systems. It is commonly installed in medium-voltage switchgear, metering panels, distribution rooms, and industrial power systems where stable three-phase voltage signals are required for meters, protection relays, and monitoring devices.
Key Ratings Snapshot
| Parameter | Value |
|---|---|
| Voltage Class | 10kV, 11kV, 12kV |
| Rated Frequency | 50Hz / 60Hz |
| System Grounding | Neutral non-effectively grounded |
| Insulation Type | Epoxy cast-resin |
| Structure | Indoor three-phase integrated |
| Secondary Output (Typical) | 100V / sqrt(3), 100V / 3, 110V / sqrt(3), 110V / 3 |
| Metering Accuracy | 0.2, 0.5, 1 |
| Protection Accuracy | 3P, 6P |
| Ambient Temperature | -5 degC to +40 degC |
| Altitude Limit | Up to 1000m above sea level |
Model Designation
- J: Voltage transformer / potential transformer
- S: Three-phase configuration
- Z: Cast-resin insulated structure
- W: Five-post structure reference
- 10: 10kV class base model; applicable to 11kV / 12kV class projects by confirmation
Construction
The JSZW-10 series features a robust three-phase integrated epoxy cast-resin insulated body suitable for indoor environments. High-voltage bushings are arranged on the upper side for primary connection, while the secondary terminal panel is located on the lower side to facilitate convenient and safe wiring. This design ensures compact installation, excellent insulation performance, and simplified three-phase wiring in standard indoor switchgear applications.
Built for neutral non-effectively grounded systems, the transformer includes primary windings (A, B, C, N), measuring secondary windings (a, b, c, n), and optional residual-voltage windings (da/dn) for earth-fault detection. The construction meets the mechanical and electrical demands of industrial and utility distribution systems requiring reliable voltage transformation for metering and protection circuits.
Technical Parameters
Service Conditions
- Installation altitude: Up to 1000m above sea level unless otherwise specified
- Ambient temperature: -5 degC to +40 degC
- Relative humidity: <=85% at 20 degC reference
- Environment: Free from explosive, corrosive, or conductive pollutants that impair insulation
- Mechanical stress: Location must be free from severe vibration, chatter, or impact
Technical Data
| Type | Voltage Ratio(V) |
Accuracy classes |
Rated output(vA) |
Limit output(vA) |
Rated insulationlevel(kV) |
|||
|---|---|---|---|---|---|---|---|---|
| 0.2 | 0.5 | 1 | 3P | |||||
| JSZW-10 | 10000/√3100/√3/100/3 | 0.2/3P | 150 | 240 | 50 | 1200 | 12/42/75 | |
| 0.5/3P | 60 | 50 | 600 | |||||
Installation & Wiring
Installation Diagram
The JSZW-10 series is wired according to system grounding mode and protection scheme. The standard wiring includes primary phase terminals (A, B, C, N) and secondary outputs for measurement (a, b, c, n) and residual voltage (da/dn). Final connections must follow the approved terminal drawing and project schematic to ensure correct operation and safety.
Outline Dimensions
| Dimension Item | Engineering Requirement |
|---|---|
| Phase spacing | Confirm per voltage class and outline drawing |
| Overall width | Confirm with switchgear layout and bushing clearance |
| Overall height | Confirm cabinet top clearance and high-voltage bushing space |
| Secondary terminal access | Reserve sufficient wiring and maintenance space |
| Mounting base | Mounting hole size and position per approved drawing |
Selection & FAQs
Selection Guide
- Confirm system voltage class: 10kV, 11kV, or 12kV based on project requirements
- Select primary voltage ratio: 10000/sqrt(3), 11000/sqrt(3), or 12000/sqrt(3)
- Choose secondary voltage: 100/sqrt(3), 100/3, 110/sqrt(3), or 110/3 per meter/relay needs
- Define accuracy class: 0.2/0.5 for metering; 3P/6P for protection or residual-voltage functions
- Verify total burden does not exceed rated output of selected winding
Frequently Asked Questions
Q1: Which accuracy class is suitable for metering and protection?
Select 0.2/3P or 0.5/3P classes based on your application. The 0.2 class provides 150VA for metering, while 3P offers 50VA for protection. Contact our engineers to finalize your accuracy class requirements.
Q2: Are there altitude restrictions for installing this transformer?
Standard installation is limited to altitudes up to 1000m above sea level. For higher elevations, derating or custom design parameters apply. Please confirm your site altitude during the inquiry stage.
Q3: What environmental conditions are required for indoor installation?
The ambient temperature must remain between -5°C and +40°C with relative humidity below 85%. Ensure the location is free from corrosive pollutants. The cast resin insulation maintains integrity under these standard indoor parameters.
Q4: Can the rated output and insulation levels be customized?
Standard JSZW-10 models feature a 12/42/75kV insulation level and up to 1200VA limit output. If your project data exceeds these standard specifications, custom configurations are available. Contact our sales team for technical evaluation.
Q5: Why must the installation environment be free from severe vibration?
Severe vibration or impact can compromise the cast resin insulation and internal connections. The equipment also requires an environment free from explosive or conductive pollutants. Please specify your exact site conditions for factory confirmation.
Q6: What factory tests are performed before shipment?
Standard routine tests are performed on every unit prior to dispatch to ensure compliance. Specific type tests or third-party certifications depend on the project contract parameters. These tests guarantee operational reliability for your switchgear.
Q7: When should the JSZW series voltage transformer be applied?
Apply this cast resin indoor transformer in 10kV AC power systems for voltage measurement. It features a standard 10000/√3 to 100/3 V ratio for indoor switchgear protection. Contact us for application-specific technical support.
Q8: How is this three-phase voltage transformer classified by the manufacturer?
This three-phase voltage transformer is classified as an indoor cast resin type. It is designed for 10kV AC systems with a 12/42/75kV rated insulation level. Reach out to our team for detailed manufacturer specifications.