Siemens Oil Insulated Combined Instrument Transformers Air-insulated switchgear

Oil-insulated combined instrument transformers are used to convert high transmission line voltages and currents (voltage up to 145kV and current up to 5000 A) to standardized low and easily measurable values, which are used for metering, protection and control of the high voltage system. As such, the need for accurate and reliable voltage and current transformation is essential.

The reliability and security of Trench oil-insulated instrument transformers is based on over 100 years of innovation with oil-insulated units operating under a wide range of environmental conditions. Oil-insulated combined instrument transformers also ensure suitable electrical insulation between high voltage and low voltage measuring equipment.

Our oil-insulated combined transformers are compliant to the latest international safety standard requirements in terms of explosion-proof, insulating material multiple chopped ageing, seismic qualification and extreme temperature conditions.

Modern production and testing facilities guarentee not only short delivery times but also a reliable operation for many years.

Oil Insulated Instrument Transformers General Features:

• Portfolio available from 72 to 145 kV
• Meet all lEC and ANSI metering and protection classes, including special core classes TPS, TPX, TPV and TPZ ones
• Rated primary Voltage up to 145 kV; rated primary current up to 5000A
• Rated Secondary Voltages: 100 V, 100:1’3 V, 100:3 V, 110 V, 110:1’3 V, …
  Rated secondary current of 1A, 2A or 5A
• Primary and/or secondary reconnection available. Rated short circuit withstand up to 200 kA peak
• Suitable also for Une Oischarge use
• Fully type tested according to international standards
• The key oil impregnated paper insulation has been optimized after lang experience based an famous Heafely-Thrench original group
• Special tests are also available to meet specific customer requirements.

Product Design:

• Oil/paper internal insulation
• External insulation with porcelain or composite insulator
• External parts made of aluminum or stainless materials
• CT core/windings located an the top of the equipment VT core/winding located an the bottom of the equipment
• Bar-type primary conductor allows higher short circuit current and avoids large voltage drop across the primary winding
• Available to withstand:
  • Effects of internal arc [according to IEC 61869 Standard]
  • Multichopped Test [according to IEC 61869 Standard]
  • Heavy seismic solicitations, according to IEC 62271, IEEE 693 and specific customers‘ requests [i.e. Chile ETG A.0.20]
• Hermetically sealed. A suitable lnox steel bellows located an the top of the Combined Transformer allows the oil volume variation and keep the internal pressure equal to ambient one in every service conditions

Siemens Transmission Products – Leader in innovations with comprehensive, connective and sustainable portfolio

Transmission products play a vital role in the energy value chain. Siemens Transmission Products provides all key elements including power transformers and distribution transformers as well as gas-insulated and air-insulated switchgear and components. Products are offered individually, bundled or with related engineering upgrade to systems. Our products offer low life cycle costs with maximum availability, highest efficiency and short commissioning times.

We are driving technology innovations not only regarding the performance of transmission products but also in the area of sustainability and eco efficiency. By merging physics and data we enable new products and applications: Sensformer® and Sensgear®. With our global factory network and leading innovations we provide the highest level of quality and reliability to our customers: TSOs, DSOs, power producers, EPCs and industrial companies.