JLS-20KV Outdoor Oil-Immersed Combined Transformer Overview

The JLS-20, JLS-22 outdoor oil-immersed combined transformer is a robust and efficient energy metering solution designed for high-voltage power systems. It integrates two sets of single-phase fully insulated voltage transformers into a three-phase V/V wiring configuration, with two current transformers connected to A and C phases in series.

This combined transformer represents an upgraded product from its predecessors, incorporating a moisture-proof device on the oil tank cover to effectively prevent external humidity from entering the oil. This feature significantly prolongs the product’s service life while providing enhanced protection against external environmental influences. Compared to older models, the JLS-20KV boasts a larger capacity, reduced volume, lighter weight, and simplified installation.

The JLS-20 is suitable for outdoor circuits with a frequency of AC50–60Hz and a rated voltage of 22kV or below. It is commonly used for metering current, voltage, and electric energy. Its application scope includes rural and urban outdoor transformer substations, miniature transformer stations, and industrial enterprise substations. Additionally, it can be equipped with active and reactive energy meters, making it a versatile solution for high-voltage power metering.

Type Designation JLS-20KV Combined Transformer

• J: Voltage transformer
• L: Current transformer
• S: Three-phase, oil-immersed type
• □: Rated voltage class

This designation highlights the key features of the JLS-20.22 outdoor oil-immersed combined transformer for efficient high-voltage metering.

Construction Overview of JLS-20KV Combined Transformer

The metering tank consists of two single-phase voltage transformers (PT) and two current transformers (CT), both of electromagnetic type. The PT and CT are securely mounted on the oil tank’s pole plate. The oil tank features a quadrate design with lifting rings on its cover for easy handling. Additional components include an oil level indicator, grounding bolt, and oil drain valve, all installed on the side of the tank for functionality and maintenance.

Service Conditions for JLS-20KV Combined Transformer

1. System: Suitable for 50Hz, 20kV/22kV three-phase AC systems.
2. Temperature: Operates from -40°C to +40°C.
3. Humidity: Monthly average ≤ 90%.
4. Altitude: ≤ 2000 meters.
5. Environment: Free from corrosive, flammable gases, and hazardous pollutants.

These conditions ensure optimal performance and longevity of the JLS-20.22 combined transformer in outdoor environments.

Technical Data for JLS-20.22 Outdoor Oil-Immersed Combined Transformer

1. Standards Compliance:
   • Metering tank: GB17201-2006
   • Current transformer: GB20840.2-2014, GB20840.1-2010
   • Voltage transformer: GB20840.3-2013, GB20840.1-2010
2. Lightning Protection:
   A zinc oxide arrester must be installed within one meter of the product to ensure protection against lightning.

Installation Dimensions for JDZC Voltage Transformers

Remark for JLS-22KV (0.2 Class, 0.2S Class) Combined Transformer

Before operating this product, ensure the unblocked respirator located in the middle of the cushion rubber on the moisture-proof device is removed. This step is critical to enable proper electrification and operation.

When Ordering, Please Specify the Following:

• Voltage and Current Ratios: Specify the required primary and secondary voltage and current ratios for the transformer.
• Accuracy Class and Secondary Output: Indicate the accuracy class (e.g., 0.2, 0.5) and the required secondary output parameters.
• Insulation Class and Environmental Conditions: Provide details regarding the required insulation class and service conditions, such as altitude, temperature, and pollution levels.
• Customizations: Specify any special requirements, such as custom metering box design, transformer dimensions, or additional features to meet specific operational needs.

For unique configurations or further assistance, please contact our technical team.

FAQs for JLS-20 Outdoor Oil-Immersed Combined Transformer

1. What are the primary applications of the JLS-20KV Combined Transformer?
This transformer is used for metering current, voltage, and energy in outdoor substations, industrial enterprises, and miniature transformer stations.

2. How does the moisture-proof device improve performance?
The moisture-proof device prevents humidity ingress, protecting internal components and significantly extending the service life of the transformer.

3. Can the JLS-20KV transformer be customized?
Yes, it can be customized to meet specific requirements, including voltage/current ratios, accuracy classes, and transformer dimensions.

4. What standards does the JLS-20KV transformer comply with?
It adheres to GB17201-2006 for metering tanks, as well as GB20840.2-2014 and GB20840.3-2013 for current and voltage transformers.

5. What maintenance is required for this transformer?
Regular inspections of the oil level and moisture-proof device are recommended to ensure consistent performance and reliability.

6. Is lightning protection included with the JLS-20KV transformer?
While the transformer itself does not include lightning protection, a zinc oxide arrester must be installed within one meter of the product to safeguard against lightning strikes.

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