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This section provides an overview for high voltage isolation transformers as well as their applications and principles. Also, please take a look at the list of 9 high voltage isolation transformer manufacturers and their company rankings. Here are the top-ranked high voltage isolation transformer companies as of April, 2025: 1.HIPOTRONICS, 2.Agile Magnetics, 3.Haas Automation, Inc..
Table of Contents
A high-voltage isolation transformer is a device that protects precision electrical equipment and the human body from abnormal voltage caused by large current inflows (lightning surges) due to lightning strikes and power line accidents.
A lightning arrester (SPD) is also used to protect equipment from abnormal voltages. While surge arresters protect electrical equipment by discharging lightning surges to the ground, high voltage isolation transformers protect equipment from lightning surges by insulating it with a transformer while discharging lightning surges to the ground.
High-voltage isolation transformers are used in a variety of locations. The following are examples of applications.
High voltage isolation transformers are also installed between the power line and the protected equipment to protect the equipment from abnormal voltage.
There are two main types of high voltage isolation transformers: isolated and ground-separated, each with different principles.
In an isolated type high voltage isolation transformers, an abnormal voltage caused by lightning surges entering from the power supply side is released to the ground by a lightning arrester, while the voltage difference between the ground and the power supply is reduced by the isolation transformer.
The ground isolation type high voltage isolation transformers reduce the inflow of lightning surges between lines and between lines and ground with multiple surge arresters, and further protect the equipment by providing high insulation with an isolation transformer. The ground isolation type is also called a surge shelter.
In both cases, the protected device side is completely insulated against lightning surges by high voltage isolation transformers, and no lightning surges flow into the device. The high-voltage isolation transformers reduce the surge transfer rate from 1/100 to 1/10,000, which is more effective than the installation of surge arresters alone. In addition, the withstand voltage to abnormal voltage is extremely high at several tens of kilovolts, providing excellent protection.
High voltage isolation transformers and surge arresters are both devices used to protect equipment from lightning surges. However, there are structural differences between high-voltage isolation transformers and surge arresters.
A lightning arrester is connected in parallel with the device to be protected, and the arrester itself is grounded. Under normal conditions, the surge arrester acts as an insulator, but when surge voltages such as lightning occur, the surge arrester becomes conductive and releases the surge voltages to the ground. ZnO (zinc oxide) is often used as a material for surge arresters.
High voltage isolation transformers are similarly grounded by ZnO on the power supply side. However, high-voltage isolation transformers have a structure in which the primary and secondary sides are insulated by a transformer. Therefore, the limiting voltage can be significantly reduced. Due to the difference in the above structures, the high voltage isolation transformers are superior to the transformer against lightning surge.
High voltage isolation transformers are superior to lightning arresters in terms of lightning protection. However, there are three disadvantages as follows.
Transformers are inductive loads, so the reactive current increases. As a countermeasure, it is possible to connect power capacitors in parallel, but the cost will still increase. The grounding pole must be separate from the load. Most loads must be grounded to the chassis, etc., but high-voltage isolation transformers require an additional grounding pole for lightning surges. If the grounding pole for lightning surges and the load side grounding pole are combined, the potential between the load wire and the ground will also rise during lightning surges. Separating the grounding poles has the disadvantage of increasing the amount of grounding burial work and complicating the system. Based on the above merits and demerits, decide whether to use a lightning arrester or high voltage isolation transformers.
*Including some distributors, etc.
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Haas Automation, Inc., established in 1983 and based in California, USA, is a manufacturer of CNC vertical machining centers, horizontal machining centers, CNC lathes and rotary products. The company's machines are categorized in vertical and horizontal mills, lathes, rotaries & indexers, multi-axis solutions and automation systems. It builds specialty machines such as 5-axis machining centers, mold making machining centers, toolroom machines, and gantry routers. It also provides operating manuals, procedures, troubleshooting guides and toolkits for its machines. The company's products and accessories comply with the ISO 9001:2015 and European Machinery Directive(CE) regulations.
Agile Magnetics, a part of Standex International (SXI) company, is a manufacturer of custom-designed electromagnetics located in Concord, New Hampshire. Its portfolio comprises high-frequency power assemblies, custom coils, and 50-60-400Hz products. They offer free design consultations to discuss customers' magnetic needs. The company is ISO 9001 and AS 9100 compliant, and its products can be meticulously tailored to meet the criteria of UL, CUL, VDE, CE, UL, and CUL, complete with the markings when required.
Hipotronics was established in 1962 and is a manufacturer of high-voltage test and measurement equipment in Brewster, New York. The company owns multiple brands, including AccelTex, Aclara, Hubbel, Worecon, and Delmar. It offers a product range that includes kilovoltmeters, hipot test equipment, AC dielectric test equipment, and DC test systems. Its electrical and electronic products are designed to be applicable for non-residential and residential construction, industrial and utility needs. They also provide OEM equipment and supplies, including isolation transformers, regulators, and DC supplies, to help original equipment manufacturers develop and deliver high-voltage products.
Transpower Electrical Equipment Co., Ltd., established in 2006, is a electrical equipment manufacturer and engineering firm. It specializes in transformer production and serves as a solution provider for the metallurgy industry, and supplies power substation equipment. The company operates its own transformer manufacturing bases in Eastern China, producing a diverse range of transformers. The company's products are known in over 48 countries and regions, and its market continues to grow. It has also expanded its portfolio to include power transmission lines and substation equipment, offering steel towers, substation structures, CT, PT, isolating switches, switchgears, and circuit breakers.
Hubbell, incorporated in the late 1800's, and based in Shelton, Connecticut, USA, is a manufacturer of electrical and electronic products. Its comprehensive product range covers standard and specialized wiring devices, rough-in electrical products, connectors, grounding solutions, lighting fixtures, and various electrical equipment for use in industrial, commercial, and institutional facilities. These products find application in diverse settings, from controlled data centers to power grids. The company's products address business challenges, improve energy efficiency, enhance safety, withstand harsh environments, and enable easier management of wiring and grounding systems around buildings.
Ranking as of April 2025
Derivation Method| Rank | Company | Click Share |
|---|---|---|
| 1 | Agile Magnetics |
21.3%
|
| 2 | HIPOTRONICS |
21.3%
|
| 3 | Haas Automation, Inc. |
20.5%
|
| 4 | Express Transformers & Controls Ltd. |
9.8%
|
| 5 | Transfo Industrie |
8.2%
|
| 6 | Hubbell. All Rights Reserved |
7.4%
|
| 7 | Transpower Electrical Equipment Co., Ltd. |
6.6%
|
| 8 | Swallow Electric Co., Ltd. |
2.5%
|
| 9 | Otowa Electric Industry Co., Ltd. |
2.5%
|
Derivation Method
The ranking is calculated based on the click share within the high voltage isolation transformer page as of April 2025. Click share is defined as the total number of clicks for all companies during the period divided by the number of clicks for each company.Number of Employees
Newly Established Company
Company with a History
*Including some distributors, etc.
*Including some distributors, etc.
| Country | Number of Companies | Share (%) |
|---|---|---|
|
United States of America
|
3 | 42.9% |
|
Japan
|
2 | 28.6% |
|
China
|
1 | 14.3% |
|
United Kingdom
|
1 | 14.3% |
107 products found
107 products
Sara Co., Ltd.
150+ people viewing
Last viewed: 12 hours ago
■Features All of our transformers comply with the RoHS Directive. Ensure creepage distance of 2.5mm between primary and secondary
Sara Co., Ltd.
150+ people viewing
Last viewed: 17 hours ago
■Features All of our transformers comply with the RoHS Directive. Creepage distance of 2.5mm is secured between 1 and 2 hours.
Aihara Electric
180+ people viewing
Last viewed: 22 hours ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
140+ people viewing
Last viewed: 1 day ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
130+ people viewing
Last viewed: 1 day ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
150+ people viewing
Last viewed: 1 day ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
180+ people viewing
Last viewed: 1 hour ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
170+ people viewing
Last viewed: 1 day ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
150+ people viewing
Last viewed: 5 hours ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
150+ people viewing
Last viewed: 1 day ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
130+ people viewing
Last viewed: 1 day ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Aihara Electric
130+ people viewing
Last viewed: 1 day ago
Protect your equipment from the wonders of lightning surges. Manufactured in a factory that has acquired quality system (ISO9001) and environmental...
Kami Electronics Industry Co., Ltd.
140+ people viewing
Last viewed: 1 day ago
A typical AC adapter has a structure that can protect up to about 1kV. However, if a surge voltage higher than this is applied, the AC adapter may ...
Pulse Electronics Co., Ltd.
140+ people viewing
Last viewed: 1 day ago
This transformer is designed to protect expensive equipment from lightning. When a lightning strike occurs on a power transmission line, a surge vo...
Kami Electronics Industry Co., Ltd.
180+ people viewing
■Features ・Trans (dropper) type AC adapter ・Excellent economy, high quality, and high reliability. ・Produced overseas under strict quality contr...
Kami Electronics Industry Co., Ltd.
160+ people viewing
Last viewed: 1 day ago
■Features ・Capacity 5W ・Input voltage AC100V ・Single output type ・Built-in protection function (overcurrent/overvoltage) ・Can be custom design...
Kami Electronics Industry Co., Ltd.
210+ people viewing
Last viewed: 3 hours ago
■Features ・Capacity 10W ・Input voltage AC100V ・Single output type ・Built-in protection function (overcurrent/overvoltage) ・Can be custom desig...
Kami Electronics Industry Co., Ltd.
130+ people viewing
Last viewed: 22 hours ago
■Features ・Capacity 24W ・Input voltage AC100V ・Single output type ・Built-in protection function (overcurrent/overvoltage) ・Can be custom desig...
CLOVER JAPAN Co., Ltd.
380+ people viewing
Last viewed: 6 hours ago
■Features ・10KV surge test cleared ・MTBF 3 million hours or more cleared - Encapsulated design to prevent dust and moisture ・Uses self-extinguis...
4 models listed
Sara Co., Ltd.
130+ people viewing
Last viewed: 10 hours ago
■Features All of our transformers comply with the RoHS Directive. Noise from AC power supplies is increasingly causing malfunctions and breakdowns ...
Sara Co., Ltd.
150+ people viewing
Last viewed: 1 day ago
■Features All of our transformers comply with the RoHS Directive. When thunderclouds occur, the electric charge induced in power lines by electros...
Sara Co., Ltd.
110+ people viewing
Last viewed: 13 hours ago
■Features All of our transformers comply with the RoHS Directive. We offer a comprehensive proposal, including peripheral circuits, with the theme...
Sara Co., Ltd.
140+ people viewing
Last viewed: 59 minutes ago
■Features All of our transformers comply with the RoHS Directive.
Pulse Electronics Co., Ltd.
180+ people viewing
Last viewed: 13 hours ago
This is a transformer that uses grain-oriented electrical steel sheets (Orient) and non-oriented electrical steel sheets (Highlight), and is mainly...
Toei Dengyo Co., Ltd.
160+ people viewing
Last viewed: 1 day ago
Converts to voltage Can be stored in a housing as a lightning-resistant transformer ■Convert to voltage (Example) 200V ⇒ 100V ■As a lightning-re...
Otowa Electric Industry Co., Ltd.
290+ people viewing
Last viewed: 10 hours ago
■Features 1. Attenuates intrusion surge to approximately 1/10,000 (10,000V→1V) 2.Reliably attenuates not only surges coming from the primary (input...
2 models listed
Otowa Electric Industry Co., Ltd.
3100+ people viewing
Last viewed: 2 minutes ago
■Features 1. Attenuates intrusion surge to approximately 1/10,000 (10,000V→1V) 2.Reliably attenuates not only surges coming from the primary (input...
3 models listed
Otowa Electric Industry Co., Ltd.
4310+ people viewing
Last viewed: 3 hours ago
■Features 1. Attenuates the intrusion surge from the primary (input power supply) side to approximately 1/100 (10,000V→100V) 2. Impulse withstand v...
2 models listed
Otowa Electric Industry Co., Ltd.
680+ people viewing
Last viewed: 21 hours ago
■Features 1.Attenuates the intrusion surge from the primary (input power supply) side to approximately 1/1,000 (10,000V→10V) 2.Ultra-thin and comp...
4 models listed
Otowa Electric Industry Co., Ltd.
160+ people viewing
Last viewed: 6 hours ago
■Features 1.Small and lightweight type 2. Attenuates the intrusion surge from the primary (input power supply) side to approximately 1/100 (10,000...
