Current Transformers for AI Data Centres | ITL UK

Current Transformers for AI Data Centres and Hyperscale Facilities: Powering the Future of Digital Infrastructure

As AI workloads continue to grow, so does the demand for reliable electrical infrastructure.

Artificial Intelligence (AI) is transforming industries worldwide, driving an unprecedented expansion in hyperscale data centres. These facilities require enormous amounts of electrical power, with many new developments demanding hundreds of megawatts of capacity. As power density increases, accurate current measurement, protection and monitoring are essential to keep AI infrastructure reliable.
Current transformers (CTs) are a critical component of this infrastructure, ensuring that electrical systems operate safely, efficiently, and reliably. From utility grid connections through to low-voltage distribution boards, CTs provide the data and protection needed to maintain continuous operation of mission-critical AI facilities.

Why AI Data Centres Place Greater Demands on Current Transformers

Unlike traditional enterprise data centres, AI facilities are characterised by:
  • Extremely high rack power densities
  • Large-scale GPU clusters
  • Rapidly fluctuating electrical loads.
  • Extensive redundancy through N+1 and 2N power architectures
  • Complex monitoring and energy management systems
  • Strict uptime requirements approaching 99.99%
These factors make the accuracy, reliability and durability of current transformers essential throughout the electrical distribution network that supports AI facilities.

Where Current Transformers Are Used

Current transformers perform several essential functions throughout a hyperscale facility, helping support the electrical performance that AI workloads demand.

Utility Incoming Supplies

CTs measure incoming current from the utility network, enabling accurate revenue metering, protection relay operation and power quality monitoring.

Medium Voltage Switchgear

Within medium-voltage switchgear, protection CTs support feeder protection, transformer differential protection and fault detection, helping safeguard valuable electrical assets.

Transformers and Substations

Instrument transformers provide vital current measurements for distribution transformers, generator transformers and on-site substations, helping ensure efficient operation and effective fault management.

Generator Systems

Standby generators are fundamental to maintaining uninterrupted operation during utility outages. Current transformers enable synchronisation, load sharing and generator protection during both normal and emergency operation.

UPS Systems

Modern UPS installations rely on accurate current measurement to optimise battery performance, monitor loading and support intelligent energy management strategies.

Low Voltage Distribution

Current transformers installed throughout low-voltage switchboards provide continuous monitoring of outgoing feeders, helping operators identify load imbalances, overload conditions and opportunities to improve energy efficiency.

Accuracy Matters

AI facilities often contain thousands of monitoring points that feed sophisticated Building Management Systems (BMS), Energy Management Systems (EMS) and Data Centre Infrastructure Management (DCIM) platforms.
Selecting the correct accuracy class is essential for:
  • Revenue and tenant billing
  • Energy efficiency reporting
  • Carbon reduction initiatives
  • Capacity planning
  • Load balancing
  • Predictive maintenance
Poor measurement accuracy can lead to incorrect energy data, inefficient asset utilisation and unnecessary operational costs, making the correct accuracy class essential.

Protection is Equally Critical

In addition to metering applications, protection current transformers also play an essential role in maintaining system resilience.
Protection CTs provide input signals for relays responsible for:
  • Overcurrent protection
  • Earth fault protection
  • Differential protection
  • Busbar protection
  • Generator protection
  • Transformer protection
Selecting the correct burden, knee-point voltage, accuracy class and saturation characteristics is fundamental to reliable protection system performance.

Engineering Considerations

Every hyperscale project presents unique engineering challenges. Factors influencing CT selection include primary current ratings, short-circuit withstand capability, accuracy class, instrument security factor, rated burden, environmental conditions, physical installation constraints and compliance with IEC 61869 and relevant project specifications.
  • Primary current ratings
  • Short-circuit withstand capability
  • Accuracy class
  • Instrument security factor
  • Rated burden
  • Environmental conditions
  • Physical installation constraints
  • Compliance with IEC 61869 and relevant project specifications
Many projects also require bespoke solutions to accommodate non-standard busbars, compact switchgear designs or specialised monitoring equipment.

Supporting Sustainable Data Centre Operations

Energy efficiency has become a key performance indicator for modern data centres, and AI facilities face increasing pressure to reduce Power Usage Effectiveness (PUE), optimise electrical efficiency and minimise carbon emissions.
High-quality current transformers enable detailed energy monitoring, allowing operators to identify inefficiencies, verify improvements and support sustainability reporting.
As data centres increasingly integrate renewable generation, battery energy storage systems (BESS) and microgrids, accurate current measurement becomes even more important for balancing power flows and maintaining system stability.

Why Choose ITL?

For over 50 years, Instrument Transformers Limited (ITL) has designed and manufactured high-quality current transformers for demanding electrical applications across utilities, industry and critical infrastructure.
Our engineering expertise enables us to support projects requiring:
  • Bespoke current transformer designs
  • Low-voltage and medium-voltage applications
  • Metering and protection CTs
  • High-current busbar solutions
  • Indoor and outdoor installations
  • Fast-turnaround prototypes
  • Technical support throughout the project lifecycle
Whether supporting new hyperscale developments or expanding existing facilities, our engineers work closely with customers to develop instrument transformer solutions tailored to their specific requirements.

Preparing for the Next Generation of AI Infrastructure

The rapid growth of AI is reshaping global electrical infrastructure, and the role of reliable instrument transformers will continue to grow as facilities become larger, more complex, and increasingly energy-intensive.
Choosing the right current transformer is not just about measuring current. It is about ensuring that protection systems operate correctly, that energy is monitored accurately, and that critical AI infrastructure remains available around the clock.
With decades of experience delivering bespoke instrument transformers, ITL is well-positioned to support consultants, EPC contractors, switchgear manufacturers, and data centre developers as they build the next generation of AI-powered infrastructure.

Speak to Our Engineers

Planning a hyperscale data centre or critical power project?
Our engineering team can help specify the most appropriate current transformer solution for your application, whether you require standard products or fully bespoke designs.
Contact ITL today to discuss your project requirements and discover how our instrument transformer expertise can support AI infrastructure.