Overview
The VOL-24 is an outdoor oil-filled single-phase voltage transformer designed for 20kV and 22kV medium-voltage distribution systems. It employs oil-immersed insulation technology, ensuring high dielectric strength and efficient thermal dissipation for reliable performance in demanding outdoor conditions.
Offering accuracy classes of 0.2, 0.5, and 1.0, the VOL-24 supports precise voltage measurement for energy metering, relay protection, and voltage monitoring. It features standard voltage ratios of 20/0.1kV and 22/0.11kV, a maximum output capacity of 500VA, and operates across an ultra-wide temperature range from -40°C to +40°C, complying with relevant IEC standards for outdoor instrument transformers.
Key Ratings Snapshot
| Parameter | Rating |
|---|---|
| System Voltage | 20kV / 22kV |
| Secondary Voltage | 100V / 110V |
| Accuracy Classes | 0.2, 0.5, 1.0 |
| Maximum Output | 500VA |
| Insulation Level | 24/50/125kV |
| Frequency | 50Hz or 60Hz |
| Phase Configuration | Single-phase |
| Insulation Type | Oil-filled (oil-immersed) |
| Ambient Temperature Range | -40°C to +40°C |
| Application Environment | Outdoor |
Construction
The VOL-24 features a robust cast-resin and metal housing enclosing an oil-immersed core-coil assembly. The primary and secondary windings are immersed in high-grade insulating oil within a sealed tank, providing excellent dielectric strength and long-term thermal stability. The design includes a conservator or expansion chamber to accommodate oil volume changes due to temperature fluctuations, ensuring consistent performance over time. All external terminals are corrosion-resistant and rated for outdoor exposure, while the tank is constructed from galvanized steel or equivalent material to withstand harsh environmental conditions including rain, dust, and extreme temperatures.
Technical Parameters
Service Conditions
- Installation position: Outdoor switchgear, substations, or distribution points
- Ambient temperature: -40°C to +40°C
- Altitude: ≤ 1000m (standard), higher altitude available on request
- Insulation: Oil-immersed
- Frequency: 50Hz or 60Hz
- Connection: Single-phase
- Maintenance: Periodic oil level and quality inspection recommended
Technical Parameters
The VOL-24 is an outdoor oil-filled single-phase voltage transformer designed for 20kV and 22kV systems. It features oil-immersed insulation, operates within an ambient temperature range of -40°C to +40°C, and is suitable for installations up to 1000m altitude (higher altitudes available on request). The unit complies with GB20840.3-2013 and IEC61869-3:2011 standards.
Voltage Transformer Data
| Type | Rated
Voltage (kV) |
Accuracy class /
Rated output (VA) |
Max.
output (VA) |
Rated
insulation (kV) |
|---|---|---|---|---|
| VOL-24 | 20/0.1 22/0.11 |
0.2-30 | 500 | 24 / 50 / 125 |
| 0.5-50 | ||||
| 1.0-100 |
Installation & Wiring
Installation Diagram
The VOL-24 Outdoor Oil-Filled Voltage Transformer is designed for secure mounting on a flat, stable base using the provided mounting holes (340/320 x 240/200mm). Primary terminals A and B are positioned at the top with insulators angled at 21°, while secondary wiring connections are made at the base. Ensure adequate clearance around the unit for ventilation and maintenance access.
Selection & FAQs
Selection Guide
- Select the correct voltage ratio: 20/0.1kV for 20kV systems or 22/0.11kV for 22kV systems.
- Choose accuracy class based on application: 0.2 for high-precision metering, 0.5 for standard metering, or 1.0 for general measurement.
- Specify rated output (30, 50, or 100 VA) according to the total burden of connected instruments and devices.
- Confirm system frequency: 50Hz or 60Hz, matching your grid requirements.
- Ensure installation type is specified as outdoor, as the VOL-24 is designed for outdoor use only.
- Verify operating temperature range (-40°C to +40°C) suits your environmental conditions.
Frequently Asked Questions
Q1: What systems is the VOL-24 voltage transformer designed for?
It is designed for 20kV and 22kV outdoor systems. The unit features single-phase oil-immersed insulation and complies with IEC61869-3:2011. Contact us for specific system integration details.
Q2: Which accuracy class is best for measurement applications?
Choose 0.2 class for 30VA, 0.5 for 50VA, or 1.0 for 100VA rated outputs. The maximum output capacity is 500VA. Specify your exact metering requirements during ordering.
Q3: Can this outdoor transformer operate in extreme cold?
Yes, it operates reliably within an ambient temperature range of -40°C to +40°C. It is suitable for outdoor switchgear and distribution points. Periodic oil level inspection is recommended.
Q4: Is this unit suitable for high-altitude installations?
The standard design is rated for altitudes up to 1000m. Higher altitude configurations are available upon request. Please provide your exact site elevation for factory engineering confirmation.
Q5: Are international certifications available for this voltage transformer?
Yes, the VOL-24 complies with GB20840.3-2013 and IEC61869-3:2011 standards. These certifications ensure reliable performance for 24kV rated insulation systems. Request the formal compliance certificate from our sales team.
Q6: How is the rated voltage ratio configured for 22kV?
The transformer is available with a 22/0.11kV rated voltage ratio for 22kV systems. This is alongside the standard 20/0.1kV option for 20kV networks. Confirm your primary voltage requirement before placing the order.
Q7: Why is oil-immersed insulation used in the VOL-24?
Oil-immersed insulation provides optimal thermal and dielectric performance for outdoor environments. This design ensures stable operation up to 24kV rated insulation. Request maintenance guidelines from our technical team.