Pretact® – React in Advance

Keeping grids resilient at any time with Siemens Transformers. Grid resilience is a widely discussed topic today. A growing population and an increasing standard of living means that energy security has never been so important. Over the last few years major outages have taken place in different areas of the globe. Today’s challenge is not only to prevent and protect transmission grids from outage risks, but also to find effective tools to use when reacting to an emergency in order to reconnect the grid as quickly and efficiently as possible.
Success Story, November 2017

First order for a bullet resistant retrofit

Siemens has received an order for the world’s first bullet resistant retrofit solution for a power transformer.

The Concept

Pretact® – The transformer resilience concept along the entire energy value chain for maximized grid stability

Maximum grid resilience is the target of all utilities and transmission operators worldwide. Siemens has developed a concept to achieve this target based on the three pillars “PREVENT”, “PROTECT”, and “REACT”. The whitepaper focuses on the challenges for the energy industry and the solutions to minimize risks and failures in transformers. Besides preventive and protective measures it also explains the Siemens-solution, which gives transformer operators the possibility to react quickly in the event that all precautions have failed.
Brochure: Grid resiliency solutions for power transformers

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Prevent operational risks

Increased transparency and lifetime
Siemens Transformers offers a complete service portfolio including the condition monitoring assessment which combines data from several measurements to analyze the condition of a fleet of transformers. Retrofit and repair services can also help to extend the lifetime of a transformer and lower operational risks.

TLM™ – Transformer Lifecycle Management

Protect against forced outages

Highly resistant protective measures
Siemens offers tailor-made protective measures. Some of them can even be installed in transformers that are already connected to the grid. Siemens Transformers have for example developed bullet-resistant protectors. Non-magnetic steel inserts prevent overheating and ensure that the transformer is GIC-safe. Siemens also promotes the use of alternative insulation fluids like ester, which has a much higher flash and fire point, therefore reducing the risk of an explosion or fire.

Bullet-resistant transformers
Transformers with DC compensation
Tank rupture-safe transformers

React to emergencies

A mobile first-aid kit
In the case of a blackout being unavoidable, Siemens Transformers have designed a strategy beyond replacement. Mobile Resilience Transformers can be quickly and easily installed, significantly reducing outage time and costs.

Variable Spare Reactors
React Rapidly to Emergencies

Mobile Resilience Transformers
Mobile Resilience Transformers are out-of-the-box products that can also be tailor-made as customers are used to for regular power transformers. In principle, all existing innovations within the design portfolio of Siemens Transformers are available.

Customer Benefits

  • A comprehensive concept to increase grid resilience and network stability
  • To prevent, protect and react at the entire energy value chain (end to end)
  • Modular feature and solution architecture to meet almost all regional or application needs, combining approved technologies and latest innovations
  • The right choice for emergencies, retrofit, upgrades and new installations for your intermediate or long-term solution to network stability challenges
  • Ecofriendly transformers for highly populated as well as rural areas
  • Save time and money while enjoying perfect peace of mind in terms of grid resilience

Infographic: Power Transformer Grid Resilience
Infographic: Distribution Transformer Grid Resilience

News & Media

Stay up to date about transformer resilience



Learn where the features of Pretact® are already in place and running – for the benefit of our customers and their consumers.
Whitepaper Download

Bypassing transformers

Our mobile resilience units are THE multifunctional pocket knife within the transformer industry: They not only serve as a means of first reaction in case of an unplanned outage, but also come in handy to bypass EHV transformers that need maintenance (planned outage). Learn how it works in our whitepaper.


Get in touch with us!

Are you interested in one or more modules of our Pretact® concept? Get in touch with us to learn how you can benefit from our innovative features and products!