SOJO Electric Co., Ltd.
Add.: Room 1111, Block D, Jiahua Plaza, Shangdi 3rd Street, Haidian District, Beijing
Tel.: +86-010-62983386
Fax: +86-010-62988464


SOJO has been focusing on the research and development of switchgear and automation equipment for power distribution network for years. We aim at launching advanced, safety and user-friendly products, and leading the technology development in the power distribution industry.

Technology advantage
Our R&D team comprises a number of senior and experienced staffs. The total number of our engineers and technicians has surpassed 130. We have increasingly potent technical ability in the domestic power distribution equipment industry, and well-known great service. SOJO has built our own processing bases for assembling and testing, sheet metal processing and cable accessories production, ensuring the safety and timely delivery of your products. Besides we are also able to provide excellent non-standard products.

Product advantage

1. All the product development, production and test follow the latest international and national standards.
2. We have the ISO9001:2008 quality management system certificate.
3. We have 3C test reports for all the low voltage products.

Environmental protection
1. The SF6 can be recycled when the SF6 insulated products need to be replaced.
2. Our solid insulated RMU doesn’t use SF6, so it is more environmentally friendly.
3. All the package of our products can be recycled.
4. We have the ISO14001: 2004 Environmental Management System certificate.

1. Safety always comes first in our product design.
2. The interlocking mechanism, high IP rating and locking mechanism follow or surpass the requirements in related standards.

Quality assurance
1. Routine factory tests are conducted for every out factory device, the test procedure includes voltage endurance, leakage, partial discharge, and high/low temperature resistance.
2. We have full record for every facility on the design, production and test.

Independent product development
After 2 years and 7 months, SOJO successfully developed a new type of environmentally friendly high-tech product-SVI type solid insulated RMU. It is developed with our own technologies and the support and assistance of related departments.

Technical advantage of SVI type solid insulated RMU
1. We use epoxy resin and silicone rubber on the solid-insulation-embedded pole to achieve completely insulation and sealing. The IP rating is IP67.
2. The usage of SF6 is totally avoided, so the product is environmentally friendly.
3. It is a small, light, smart, and flexible product. The performance is quite reliable, while the operation is very safe.
4. We have international patent technology for its production. This product is also the first of its kind.
5. It has been subjected to the whole KEMA test according to the IEC standards.

Application advantage of SVI type solid insulated RMU
Low temperature area
The design of solid ring main units doesn’t need SF6. So the potential problem caused by insulation gas being liquefied under low temperature can be avoided.

Plateau area
Due to the absence of SF6, the problems caused by the big pressure difference between the inside and outside of the gas tank in high altitude areas can be avoided.

Explosion forbidden places
The switch adopts vacuum interrupter sealed with epoxy resin bushing which can prevent the gas exposure and explosion.

Potential transformer (PT) on-site installing cases
It is convenient to upgrade the existing RMU.

Basement with workers 
The density of SF6 is 5 times higher than air on the same condition. So if the SF6 in a traditional RMU leaks out, it will accumulate in low area, so the workers there could be harmed or suffocated.

Frequent switching operation situation
Our product can endure more than 10,000 times of switching operations.

Areas with high requirements for environmental protection
Our solid insulation RMU doesn’t contain SF6, which is a kind of greenhouse gas.

Coastal area
The well sealed mechanism and professional high salt mist tester can ensure the long service life in costal area.

Windy and sandy area 
The IP rating of the solid insulated RMU reaches IP67. The control loop compartment is specially treated, so our product can work in windy and sandy area for a long time.

Power distribution network automation 
The build-in SOJO electric SJDA2000 power distribution automation products or other optional products lead to automatic power distribution. The load switches can switch off in a extremely short period of time, contributing to the power distribution automation.

Environmental protection advantage
SOJO has been taken our responsibility to the environment seriously. We keep focusing on related research, aiming at providing advanced, energy-saving and environmentally friendly electric products.
We have taken a range of measures during the design, production, marketing, and recycling of our products to achieve eco-friendly performance
We have composed strict regulations on our products’ recycling procedure, and we track every product down to the end.

Quality advantage
Our professional technicians and high precision equipment can guarantee desirable precision, production speed and productivity.

System certification
1. ISO 9001: 2008 Quality Management System certificate
2. ISO 14001: 2004 Environmental Management System certificate
3. OHSAS 18001: 2007 Occupational Health and Safety Management System certificate
4. ERP management for every functional department
5. GB/T19001: 2000 and ISO9001: 2000 certificates for the business department, marketing department, production department and finance department.
6. ISO14001: 2004 certificate for the production system, testing system and logistic system.

Testing system
Systematically tests will be conducted on every product before they go to the market. The tests include:
1) Automatic leakage test;
2) Corrosive salt spray test;
3) Closing and opening speed test;
4) Speed measuring;
5) Power-frequency voltage-withstand test;
6) High/low temperature test (for some key components);
7) Overflow test;
8) Partial discharge test (for parts of the components);

The quality inspection department will record the systematical test information of every semi-finished and finished products, and release inspection certificate and test report for the qualified products.