20kV 44kV 145kV 150kV Three Phase Oil-Immersed Neutral Earthing Transformer Custom Factory

Name: 20kV 44kV 145kV 150kV Three Phase Oil-Immersed Neutral Earthing Transformer Custom Factory
Brand: Wenzhou Rockwill Electric Co., Ltd.
SKU: 16923
Price: 1.99 USD
Availability: InStock

Wenzhou Rockwill Electric Co., Ltd.

17yrs 700++ staff 108000m²+m² US$150000000+ China

Wenzhou Rockwill Electric Co., Ltd.

17yrs 700++ staff 108000m²+m² US$150000000+ China

Attributes Description Documentation Resource Library Supplier

Key attributes

Brand	ROCKWILL
Model NO.	20kV 44kV 145kV 150kV Three Phase Oil-Immersed Neutral Earthing Transformer Custom Factory
Rated voltage	20kV
Rated capacity	100kVA
Phases	Three-phase
Series	JDS

Product descriptions from the supplier

Description

Product Overview

As a pioneer and the first professional original manufacturer in China's earthing transformer industry, decades of dedicated focus have enabled us to accumulate strong technical strength and even establish the fundamental standards for industry development. Covering the entire chain from breakthroughs in core technological innovation to large-scale production and delivery, we have built an independent ecological system. With leading and stable product performance as well as extremely reliable quality, we have become a trusted choice in the field of power grid construction.

This series of three-phase oil-immersed neutral earthing transformers is a customized core equipment specifically designed for medium- and high-voltage power systems, covering voltage classes from 20kV to 150kV and adopting a fully sealed oil-immersed structure. Through factory-customized production, the product can be flexibly configured according to the user's grid parameters, installation environment, and protection requirements, providing a reliable artificial neutral point solution for ungrounded or low-current grounded systems. It effectively suppresses arc grounding overvoltage and enhances grid operational stability and safety.

Basic Info

Some of these earthing transformers cover voltage levels including：3.3kV / 6kV / 11kV / 15kV / 20kV / 22kV / 30kV / 33kV / 34.5kV / 36kV / 44kV / 66kV / 88kV / 110kV / 132kV / 145kV / 150kV / 220kV / 275kV / 330kV / 400kV, etc. The current withstand time ranges from 1s, 2s, 3s, 5s, 6s, 8s, 9s, 10s, 30s, 60s, 1hour to 2hours, and customization is available.

Model NO.	JDS	Core	Core-type Transformer
Cooling Method	Oil-immersed Type Transformer	Winding Type	Two-winding Transformer
Certification	ISO9001	Usage	Power Transformer
Frequency Characteristics	Power Frequency	Shape of Core	Ring
Brand	Rockwill	Transformer	Earthing Transformer
Rated Capacity	100 kVA	Color	Grey or Customized
Coil Material	Copper	Losses	Low Losses
Transformer Phase	3 Phase	Iron Core	Power Transformer Core
Transport Package	Wooden Case	Specification	CTQC type tested
Trademark	Rockwill	Origin	Zhejiang, China
HS Code	85042100	Production Capacity	5000MAV/Year

Key Specifications

Model: JDS-100/20
Capacity: 100kVA
Voltage: 20kV
Frequency: 50/60Hz
Winding: Copper two-winding design
Core: Ring-shaped silicon steel
Cooling: ONAN (Oil Natural Air Natural)
Impedance: Low zero-sequence impedance (<10Ω)
Certification: ISO 9001, CTQC tested

Technical Advantages

Superior Grounding Performance

Specially designed winding configuration for optimal neutral point stability
Withstands 100A short-circuit current for 10 seconds
Low zero-sequence impedance ensures effective fault current diversion

Advanced Oil-Cooled Design

Hermetically sealed corrugated tank prevents oil contamination
Mineral oil insulation with -30°C to +40°C operating range
Optional Midel 7131 ester fluid for enhanced fire safety

Robust Construction

Heavy-gauge steel tank with anti-corrosion treatment
Precision-engineered core with reduced magnetic losses
Vibration-resistant mounting system

Smart Protection Features

Standard Buchholz relay for internal fault detection
Pressure relief device for overload conditions
Oil level indicator with alarm contacts

Application Scenarios

Industrial Power Systems

Ideal for manufacturing plants with sensitive equipment
Protects against ground faults in 20kV distribution networks
Suitable for harsh industrial environments

Renewable Energy Installations

Wind farm collector substations
Solar park step-up stations
Biomass power generation facilities

Infrastructure Projects

Metro power supply systems
Airport electrical networks
Hospital backup power systems

Why Choose Rockwill?

20+ years of transformer manufacturing expertise
Custom engineering support available
Complete type test reports provided
Global service network with 24/7 technical support
Environmentally conscious production processes

FAQ for

Q: What are the core international standards governing the design, production and testing of earthing/grounding transformers, and what are their respective focuses?

At present, the mainstream global standards are divided into the IEEE system and the IEC system. Domestic standards mostly refer to IEC and are customized according to national conditions. The core standards and their respective focuses are as follows:

IEEE 32: The dominant standard in North America, focusing on the "fault performance" of earthing/grounding transformers. It details the core requirements such as zero-sequence impedance test methods, short-time withstand current calculation, and mechanical strength verification, and is a key basis for the selection of high-voltage and extra-high voltage systems.
IEC 60076 series: The core international general standard. Among them, IEC 60076-8 specifically regulates the winding design, impedance requirements and test methods of earthing/grounding transformers; IEC 60076-1 defines the general requirements for insulation media; IEC 60076-2 specifies the classification and performance indicators of cooling methods; IEC 60076-5 specifies the test specifications for short-time withstand capacity, forming a complete technical system.
ANSI C57.12/IEC 60038: ANSI C57.12 supplements the manufacturing process requirements of earthing/grounding transformers in North America; IEC 60038 unifies the nominal values of voltage levels to ensure the compatibility of products from different countries.
Domestic relevant standards: Such as GB/T 6451, which refers to the IEC 60076 series and puts forward supplementary requirements on efficiency, temperature rise and harmonic resistance according to the characteristics of China's power grid.

Q: What is the function of the auxiliary winding of an earthing/grounding transformer, and what are its common specifications?

The auxiliary winding is an optional configuration of the earthing/grounding transformer. Its core function is to "provide low-voltage power for local loads in the substation", avoiding the additional configuration of a dedicated distribution transformer and reducing system cost. Its design follows the principle of "small capacity and standardization". Common specifications are: the voltage level can be 400V/230V (adapting to domestic and European standards) or 480V/277V (adapting to North American standards), and the capacity is usually no more than 200kVA, which can meet the power demand of auxiliary equipment such as control circuits, lighting and ventilation in the substation. It should be noted that the auxiliary winding only serves as an "auxiliary function" and does not affect the core grounding performance of the earthing/grounding transformer.

Know your supplier

ROCKWILL

Wenzhou Rockwill Electric Co., Ltd.
17yrs 500-1000 employees 108000m²+m² US$150000000+ China

Wenzhou Rockwill Electric Co., Ltd.

17yrs 500-1000 employees 108000m²+m² US$150000000+ China

Online store

On-time delivery rate

Response time

100.0%

≤4h

Company overview

Workplace: 108000m²m² Total staff: 700+ Highest Annual Export(usD): 150000000

Workplace: 108000m²m²
Total staff: 700+
Highest Annual Export(usD): 150000000

Services

Business Type: Design/Manufacture/Sales

Main Categories: High Voltage Electrical Apparatus/Electric transformer

Whole life care manager

Whole-life care management services for equipment procurement, use, maintenance, and after-sales, ensuring safe operation of electrical equipment, continuous control, and worry-free electricity consumption.

The equipment supplier has passed platform qualification certification and technical evaluation, ensuring compliance, professionalism, and reliability from the source.

Negotiable

Pricing calculator

Model

JDS-100KVA-20KV

Warranty by

Whole life care manager

The equipment supplier has passed platform qualification certification and technical evaluation, ensuring compliance, professionalism, and reliability from the source.

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