Description of 35KV epoxy resin casting combined transformer

The 35KV epoxy resin casting combined transformer, also known as a metering tank, is designed for three-phase AC50Hz circuits with a rated voltage of 35kV. It is suitable for voltage, current, and energy measurement, as well as protective relaying. This product is widely used in urban and rural outdoor transformer substations and industrial power systems.

By integrating active and reactive energy meters, this high-voltage power metering tank offers a modern replacement for traditional oil-immersed transformers, providing enhanced performance and reliability for power distribution networks.

Type Designation of JLSZW-35 Combined Transformer

• J: Voltage transformer
• L: Current transformer
• S: Three-phase
• Z: Epoxy resin casting type
• W: Outdoor device
• □: Design serial number
• 35: Rated voltage class (kV)

This clear designation highlights the key features and structure of the JLSZW□-35 outdoor epoxy resin casting type combined transformer.

Service Conditions of JLSZW-35

1. This product is suitable for three-phase AC power systems of 35kV at a frequency of 50Hz.
2. Ambient temperature: -40°C to +40°C.
3. Air relative humidity: Monthly average ≤ 90%.
4. Altitude: Installation altitude ≤ 2000m.
5. Surrounding air must be free from corrosive gases or flammable pollutants.

Construction of JLSZW-35kv Combined Transformer

JLSZW-35kv Combined Transformer feature an outdoor epoxy resin casting type, with a fully sealed and post-type mechanism. The use of epoxy resin provides excellent benefits such as anti-electric-arc properties, UV resistance, anti-aging performance, and extended service life.

The Combined Transformer consists of two single-phase, fully insulated voltage transformers, arranged in a “V/V” wiring mode. Additionally, two current transformers are connected in series to the A and C phases. The secondary coil of the current transformer includes a tap, allowing for flexible current adjustments.

For enhanced configurations, an upgraded model offers three-phase, three-component Y/Y wiring mode, designed as a high-voltage power metering tank.

The metering box housing is made of durable iron and can be customized to meet specific user requirements, including size, insulation enhancements, and corrosion-resistant treatments to suit diverse environmental and operational conditions.

Technical Data for JLSZW-35kv Combined Transformer

1. The combined transformer complies with provisions outlined in GB20840.4-2015 《combined transformer》.
2. The current transformer conforms to provisions in GB20840.2-2014, GB20840.1-2010 《current transformer》.
3. The voltage transformer adheres to provisions in GB20840.3-2013, GB20840.1-2010 《voltage transformer》.
4. A zinc oxide arrester must be installed within one meter of the installation site for lightning protection.
5. For CT and PT parameters, please refer to the following two tables for detailed specification

Voltage Transformer Technical Data

Type	Rated Voltage Ratio (V)	Accuracy Classes	Rated Output (vA)	Limit Output (vA)	Rated Insulation Level (kV)
JLSZW-35	35000/100	0.2	30	500	42/95/195
		0.5	50

Current Transformer Technical Data

Type	Rated Voltage Ratio (A)	Accuracy Classes	Rated Output (vA)	Rated Short-Time Thermal Current(kA)	Rated Dynamic Current (kA)	Rated Insulation Level (kV)
JLSZW-35	5~200/5	0.2S	10	100 I1n	2.5 I1th	42/95/195
		0.2	10

Note: For special transformer parameters such as current ratio, accuracy, and transformer dimensions, please feel free to contact our technical team for customized solutions and discussions.

Outline and Dimensions of Installation

When Ordering, Please Specify the Following:

1. Voltage Ratio and Current Ratio: Specify the required voltage and current ratios for the CT and PT.
2. Accuracy Class and Secondary Output: Indicate the accuracy class (e.g., 0.2, 0.5) and the required secondary output parameters.
3. Insulation Class and Service Conditions: Provide details regarding the required insulation class and the environmental conditions where the product will be installed.
4. Custom Appearance: The appearance of the metering box can be customized to fit specific application scenarios.
5. Special Requirements for CT and PT Parameters: If there are unique requirements for transformer precision, current ratios, or appearance, customization options are available. Please contact us for tailored solutions.

Technical FAQs for JLSZW-35 Combined Transformer

1. What are the primary applications of the JLSZW-35 epoxy resin casting combined transformer?
   It is designed for voltage, current, and energy metering in 35kV three-phase systems, ideal for urban grids, rural substations, and industrial networks.
2. How does the transformer ensure reliability in outdoor environments?
   Its epoxy resin insulation and fully sealed construction provide resistance to UV, aging, pollution, and moisture, ensuring stable performance.
3. Can the 35kV transformer be customized?
   Yes, customization options include voltage and current ratios, accuracy classes, transformer dimensions, and appearance adjustments for specific applications.
4. What maintenance is required for the transformer?
   Regular cleaning of the surface and inspection of operational parameters ensure long-term reliability, with minimal maintenance needed.
5. What insulation and safety standards does the transformer comply with?
   It meets GB20840.4-2015 standards, offering a rated insulation level of 42/95/195kV and provisions for lightning protection using zinc oxide arresters.
6. Why choose this transformer over traditional oil-immersed models?
   The epoxy resin casting design eliminates oil, reducing environmental hazards, while offering superior durability, minimal maintenance, and enhanced precision for modern power systems.

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