Question 1

What are medium- and high-voltage transformers and MV switchgear used for?

Accepted Answer

Medium- and high-voltage transformers change voltage levels to support efficient electricity transmission and distribution. MV switchgear controls, protects, and isolates medium-voltage circuits and electrical equipment. Together, transformers and switchgear help maintain safe and reliable power distribution in industrial facilities, infrastructure, utilities, renewable energy systems, and other demanding electrical installations.

Question 2

Which transformer should I choose: a cast resin or an oil-insulated transformer?

Accepted Answer

Choose a cast resin transformer when fire safety, low maintenance, and suitability for demanding indoor environments are key requirements. Oil-insulated transformers can be installed indoors or directly outdoors, depending on the transformer design and site requirements. The right solution depends on the required power rating, voltage levels, installation environment, available space, load profile, and applicable safety requirements. IMEFY cast resin transformers are designed for reliable operation in environments affected by moisture, industrial or marine pollution, and elevated fire risk.

Question 3

What transformer power ratings does Finn Electric supply?

Accepted Answer

Finn Electric supplies IMEFY cast resin transformers in standard ratings from 100 to 3,150 kVA, with special models available up to 25 MVA. Hermetically sealed oil-insulated transformers are available from 25 to 2,500 kVA, while models with expansion tanks are available from 3,150 to 8,000 kVA. Special transformers are also available upon request.

Question 4

Can Finn Electric supply a transformer customized for a specific project?

Accepted Answer

Yes. Finn Electric can supply special transformers and project-specific configurations according to the application's technical requirements. Transformer selection can account for the required power rating, voltage levels, insulation technology, cooling method, installation conditions, load characteristics, dimensions, accessories, and applicable standards.

Question 5

Are high-voltage power transformers available for large transmission projects?

Accepted Answer

Yes. Finn Electric supplies CHINT high-voltage power transformers, including models for demanding power transmission applications. CHINT manufactures natural ester oil-immersed power transformers for voltage levels up to 750 kV. Finn Electric and CHINT work together during the project design phase to define suitable specifications and support efficient delivery and commissioning.

Question 6

What are the main specifications of Finn Electric's RB medium-voltage switchgear?

Accepted Answer

The modular RB medium-voltage switchgear has a rated current of 630 A and a rated short-circuit current of 16 or 20 kA for one second. It uses an ABB VD4R vacuum circuit breaker and SF6-insulated load-break switches. The standard protection relay is the ABB REF601, while selected protection relays from ABB, Schneider Electric, or Arcteq can also be used.

Question 7

Can RB medium-voltage switchgear be configured for different protection and control requirements?

Accepted Answer

Yes. RB medium-voltage switchgear can be equipped with options such as motor-operated mechanisms, auxiliary contacts, voltage indicators, short-circuit and earth-fault indicators, low-SF6-pressure gauges, and tripping coils. The final configuration can be selected according to the project's protection, control, indication, and operating requirements.

Question 8

Does Finn Electric support transformer projects from specification to commissioning?

Accepted Answer

Yes. Finn Electric works with its manufacturing partners during the project design phase to identify appropriate transformer specifications. For CHINT transformer projects, this cooperation supports project-specific design as well as efficient delivery and commissioning.

Mid and High Voltage Transformers and MV Switchgears