Overview
The JSZV12-10R series combined voltage transformers are precision electromagnetic instruments designed for accurate voltage measurement, energy metering, and auxiliary power supply in 10 kV class medium-voltage AC power systems. These fully-enclosed, epoxy resin cast units integrate dual secondary outputs with built-in high-voltage fuse protection on each phase, delivering galvanically isolated signals proportional to the primary voltage via electromagnetic induction.
Operating on Faraday’s law, the transformer provides a 100 V output for revenue-grade metering and a 220 V output for powering control circuits, protection relays, and monitoring equipment. The compact V-connection design uses two single-phase units suitable for indoor switchgear, ring main units, and distribution panels, ensuring system reliability and simplified installation.
Key Ratings Snapshot
| Parameter | Value |
|---|---|
| System voltage class | 10 kV (indoor) |
| Rated frequency | 50 Hz (60 Hz optional) |
| Voltage ratio | 10000/100 V or 10/0.1/0.22 kV |
| Secondary outputs | 100 V (metering), 220 V (auxiliary) |
| Accuracy classes | 0.2, 0.5 |
| Rated burden | 20 VA (0.2 class), 60 VA (0.5 class) |
| Max output (short-time) | 500-600 VA |
| Insulation level | 12/42/75 kV (Um/Ud/Up) |
| Configuration | Three-phase V-connection (two units) |
| Fuse protection | Integrated HV fuses on A/B/C phases |
Model Designation
- J: Combined instrument transformer (voltage + protection)
- S: Indoor type (室å )
- Z: Cast-resin (epoxy) insulated, fully enclosed structure
- V: Voltage transformer function
- 12: Design series / platform iteration
- 10: Voltage class (kV)
- R: Integrated fuse protection (çæå¨)
Construction
The JSZV12-10R features a fully-enclosed epoxy resin cast construction with premium cold-rolled silicon steel laminated cores, ensuring superior dielectric strength, moisture resistance, and long-term thermal stability. This robust design is optimized for indoor switchgear environments, providing reliable performance under continuous operation while resisting contamination, tracking, and aging.
Integrated high-voltage fuses on all three primary windings offer coordinated short-circuit protection and prevent fault propagation. Secondary terminal blocks are easily accessible for fuse replacement without de-energizing the system, enhancing maintenance safety and operational continuity.
Technical Parameters
Service Conditions
- Installation environment: Indoor only
- Altitude: <= 1000 m (higher on request)
- Ambient temperature: -5 deg C to +40 deg C
- Relative humidity: <= 80% (no condensation)
- Environmental conditions: Free from corrosive gases, explosive media, conductive dust, severe vibration, or mechanical shock
Technical Data
| Type | Rated Voltage Ratio (V) |
Accuracy Class & Rated Output (VA) |
Max Output (VA) |
Rated Insulation Level (kV) |
|---|---|---|---|---|
| 0.2 / 0.5 / 1 / 6p | ||||
| JSZW3-10 | 10000/√3/100/√3/100/√3 | 15 / 30 / 60 / 50 | 300 | 12/42/75 |
| JSZW3-6 | 6000/√3/100/√3 | 15 / 30 / 60 / 50 | 300 | 7.2/32/60 |
| JSZW3-3 | 3000/√3/100/√3 | 15 / 30 / 60 / 50 | 300 | 3.6/20/40 |
Installation & Wiring
Installation Diagram
The JSZV12-10R is typically installed as two single-phase units in a V-connection (open-delta) configuration for three-phase systems. Primary terminals connect to A-N and B-N (or A-B-C in wye systems), while secondary terminals deliver 100V for metering (a-x) and 220V for auxiliary power (a1-x1). Proper phase identification and grounding of one point per secondary circuit are mandatory. Fuse replacement is performed via accessible secondary terminals without system shutdown, following manufacturer procedures.
Outline Dimensions
| Dimension | Value (mm) |
|---|---|
| Height | As per dimensional drawing |
| Width | As per dimensional drawing |
| Depth | As per dimensional drawing |
| Mounting hole pattern | As per dimensional drawing |
| Primary terminal clearance | Per switchgear integration spec |
Selection & FAQs
Selection Guide
- Confirm system voltage class: 10 kV, 6 kV, or 3 kV
- Select output configuration: dual (100V + 220V) or single (100V only)
- Choose accuracy class: 0.2 for revenue metering, 0.5 for general monitoring
- Calculate total burden (VA) for each secondary circuit based on connected loads
- Verify insulation level matches switchgear requirements (standard: 12/42/75 kV)
- Specify fuse rating if custom coordination with protection scheme is needed
Frequently Asked Questions
Q1: Can this combined voltage transformer be installed outdoors?
No, this transformer is strictly for indoor installation. It requires an environment free from corrosive gases, conductive dust, and severe mechanical shock. Please contact us for outdoor-rated alternatives.
Q2: Which accuracy class is required for revenue metering?
Select the 0.2 accuracy class for precise revenue billing applications. This class provides a rated output of 15 VA at the specified voltage ratios. Confirm your exact burden requirements with our engineering team.
Q3: What medium-voltage applications suit this combined transformer with fuse?
It is ideal for indoor medium-voltage switchgear requiring voltage measurement, protection, and integrated fuse protection. The JSZW3 series supports 3kV, 6kV, and 10kV distribution networks. Maximum output reaches 300 VA.
Q4: What is the maximum operating altitude for this transformer?
Standard models are rated for altitudes up to 1000 meters. For installations at higher elevations, derating or custom design is required. Submit your exact site altitude for factory evaluation.
Q5: Are routine factory tests provided before shipment?
Yes, routine tests including insulation resistance and voltage ratio checks are conducted on every unit. Specific type tests or special acceptance tests are subject to confirmation. Request the test certificate template prior to ordering.
Q6: When should I specify a dual-output model?
Specify dual-output models when your switchgear requires both 100V for metering and 220V for auxiliary power. Single-output variants supply 100V exclusively. This ensures proper power distribution for secondary circuits.
Q7: Are custom voltage ratios available for specific switchgear?
Yes, non-standard voltage ratios and specific insulation levels can be customized. Standard models cover 3kV, 6kV, and 10kV systems. Contact our sales team with your technical specifications for a customized quote.