Modern electrical systems require high-performance components that support efficiency, safety, and operational reliability. Current measurement is one of the most critical aspects of power systems, and errors at this stage can lead to cascading issues in protection, monitoring, and billing. Toroidal Current Transformers serve as the backbone of accurate current sensing. Yet, most commercially available CTs are generic, mass-produced devices that often fail to meet the demanding operational expectations in complex power networks.
Frigate’s Toroidal Current Transformers are engineered solutions, not catalog parts. These devices address precise challenges in the power ecosystem—from harmonic distortions to unpredictable transient events. With design strategies based on actual load profiles, environmental conditions, and compliance requirements, Frigate’s CTs set a higher benchmark.
Why Frigate’s Toroidal Current Transformers Perform Better Than Standard Off-the-Shelf Units?
Standard current transformers target generic conditions. But modern grids are complex—loaded with harmonics, transients, and non-linear loads. Measurement accuracy and protection reliability demand more than mass-produced designs.
Frigate’s Toroidal Current Transformers are precision-engineered for real-world electrical environments. Core behavior, flux limits, and compliance are fine-tuned per application. With high accuracy under dynamic conditions, these CTs ensure consistent signal fidelity and protection performance. Below are the technical differentiators that set Frigate apart from standard offerings –
Application-Calibrated Flux Density Optimization
Real-world electrical environments involve variable current patterns due to harmonics, system overloads, and transient anomalies. Generic CTs fail to reflect these conditions accurately because they rely on one-size-fits-all flux density characteristics. Frigate addresses this challenge using advanced magnetic field simulation tools, core design customization, and dynamic B-H curve modeling. This enables precise tuning of the magnetic core to respond linearly over a broad operating spectrum, ensuring that early core saturation is avoided, and waveform distortion is minimized under non-linear loading conditions.
By applying simulation-led calibration, Frigate tailors the flux density range to suit actual field usage. This optimization allows their Toroidal Current Transformers to deliver stable and distortion-free current measurements across a wide range of fault, peak, and harmonic-rich scenarios. Whether installed in industrial facilities, renewables, or grid substations, Frigate CTs preserve signal integrity, reduce noise interference, and improve downstream analytics.
High Accuracy Across Load Range
Mass-market CTs are typically calibrated for peak rated loads and often deliver poor accuracy at low or mid-range currents. This is problematic for renewable installations, part-load operations, and dynamic load profiles where power factors shift continuously. Frigate designs its Toroidal Current Transformers to achieve high accuracy over an extended load range—from 1% to 120% of rated current—eliminating the blind zones associated with off-the-shelf options.
Such wide-range accuracy is validated using traceable calibration protocols and third-party testing. Frigate CTs meet or exceed IEC 61869-2 Class 0.2 and 0.5S requirements across real-world load conditions. This precision enhances metering, fault recording, and control performance while reducing long-term cumulative measurement errors in multi-stage monitoring and automation frameworks.
Fast Transient Capture
Transient fault currents often last for a fraction of a cycle but play a critical role in triggering protective devices. Standard CTs made from silicon steel cores exhibit hysteresis and residual magnetism, causing delay and distortion in transient response. Frigate overcomes this by using low-coercivity core materials like amorphous and nanocrystalline alloys. These cores respond almost instantly to abrupt changes in current without introducing signal lag or remanence bias.
Frigate’s fast-response core design enables precise recording of asymmetrical and high di/dt fault currents. Their Toroidal Current Transformers achieve sub-cycle transient tracking, which enhances protection relay coordination, breaker timing, and fault analysis. These CTs contribute directly to faster fault clearance, reduced arc energy exposure, and improved safety in mission-critical installations.
Low Burden Performance
Digital metering devices and microprocessor-based protective relays operate with very low input burdens—often below 0.2 VA. Generic CTs, when connected to low-burden devices, either saturate prematurely or deliver distorted waveforms. Frigate resolves this issue by designing its CTs with low-resistance windings, optimal magnetic path lengths, and finely tuned impedance characteristics that work seamlessly at ultra-low burdens.
The result is signal accuracy without needing auxiliary amplifiers or burden-matching accessories. Frigate’s Toroidal Current Transformers maintain ratio fidelity and linear response even when interfaced with compact digital meters or low-power current inputs. This ensures reliable performance in smart grid environments, IoT-enabled panels, and advanced metering infrastructure (AMI).
Reduced Phase Displacement
Phase displacement errors cause incorrect power factor calculations, affecting reactive power billing and system loss assessments. Standard CTs often suffer from core-related phase shifts, especially at low current levels. Frigate mitigates this using magnetically uniform cores, precision winding geometry, and active phase compensation techniques during calibration.
These engineering controls reduce phase displacement to below 5 minutes at rated load, far outperforming many industry benchmarks. Frigate CTs ensure synchronous phase tracking across multiple current channels, which is critical in applications like vector-based protection, PQ monitoring, and energy auditing. The reduction in displacement directly translates to improved billing transparency and energy optimization.
Enhanced Electromagnetic Compatibility (EMC)
Power environments are increasingly susceptible to electromagnetic interference (EMI) due to proliferation of switching devices, VFDs, and wireless communications. Many CTs act as unintentional EMI sources or victims due to poor shielding or layout. Frigate applies layered shielding strategies, grounded magnetic paths, and high-permeability materials to suppress both conducted and radiated EMI.
All Frigate CTs are tested under IEC 61000 series to validate immunity and emission thresholds. Their Toroidal Current Transformers operate reliably in high-EMC zones like data centers, industrial automation panels, and railways. EMC integrity ensures CT signals remain clean and interpretable even when installed adjacent to power electronics or RF-emitting equipment.
Harmonic Linearity
Distorted waveforms with high harmonic content are common in today’s power systems. Generic CTs are designed for sinusoidal signals and exhibit severe non-linearity when subjected to harmonics beyond the 13th order. Frigate CTs are tested across harmonic spectrums up to the 50th order, ensuring ratio accuracy remains within specification under real-world non-linear loading.
This harmonic linearity enables correct measurement in environments dominated by VFDs, UPS systems, and solar inverters. With linear performance across a wide frequency range, Frigate’s Toroidal Current Transformers facilitate accurate power quality monitoring, harmonic filtering, and compliance reporting. These capabilities are critical for utilities enforcing THD-based penalties and maintaining power grid health.
Thermal Stability in Wide Temperature Ranges
Outdoor and industrial environments expose CTs to harsh temperatures from -40°C to +85°C. Standard units often show drift in ratio or phase error under these conditions due to material expansion, insulation breakdown, or magnetic core shifts. Frigate uses thermally rated materials, epoxy composites, and heat-resilient magnetic cores to guarantee operational consistency across the full temperature band.
Temperature compensation is integrated at the design stage, with core selection, winding insulation, and bobbin design validated via thermal cycling tests. Frigate CTs maintain their accuracy class under prolonged thermal stress, which is vital for substations, wind farms, and oil & gas facilities where ambient temperatures vary significantly.
Robust Dielectric Withstand Capability
Medium-voltage installations often face voltage surges and insulation stress due to switching and lightning events. Many CTs fail due to dielectric breakdown, especially under wet or polluted conditions. Frigate designs its CTs with Class F insulation systems, layered dielectric barriers, and encapsulation methods that exceed IEC 61869 and IEEE C57.13 withstand requirements.
Each unit undergoes type testing at multiple voltage levels, including impulse and power frequency withstand tests. The enhanced dielectric strength ensures long-term reliability even in coastal, dusty, or chemically aggressive environments. This robustness extends the service life and reduces insulation-related maintenance or failure risks.
Compact Form Factor with Custom Mounting Options
Space constraints in electrical panels, MCCs, and switchgear require CTs that offer both compactness and flexibility. Standard CTs are often too bulky or come with fixed mounting options that complicate layout planning. Frigate addresses this with a modular design approach, offering multiple form factors, winding configurations, and mechanical mounting accessories.
Their Toroidal Current Transformers are available in various ID ranges, heights, and enclosure types—suitable for both retrofits and new installations. Panel integrators benefit from simplified routing, optimized panel space, and faster installation. Custom brackets, DIN-rail kits, and enclosure-ready designs ensure mechanical and electrical compatibility.
Global Standards Compliance and Testing
Compliance with global standards is not just a checkbox but a functional requirement for grid compatibility, audits, and certifications. Frigate ensures that every CT meets IEC 61869, IEEE C57.13, and ANSI C12.20 standards. Compliance is verified through a multi-stage testing regime that includes routine, type, and special tests.
Test reports include core magnetization curves, ratio and phase errors, insulation resistance, and mechanical endurance data with complete traceability. This level of documentation supports deployment in regulated markets, utility procurement, and industrial audits. Customers gain assurance that Frigate CTs will pass grid interconnection tests and withstand field inspections.
Long-Term Stability and Low Drift
CTs deployed in critical infrastructure must maintain performance over decades. Standard units exhibit gradual drift due to moisture ingress, thermal cycling, and magnetic aging. Frigate uses epoxy resin encapsulation, UV-stable coatings, and moisture-proof designs to shield against environmental stressors.
Their CTs undergo accelerated life testing to simulate 10+ years of operation. Drift remains below 0.05%, ensuring that calibration remains within class limits without periodic adjustment. This longevity minimizes operational downtime, recalibration costs, and regulatory non-conformance risks in energy-intensive industries.
Conclusion
Frigate’s Toroidal Current Transformers combine application-specific magnetic engineering, advanced core materials, and robust mechanical-electrical design to solve key pain points faced in modern energy systems. They deliver high accuracy across dynamic load conditions, fast transient detection, harmonic fidelity, and resilience in tough environments—all while remaining compliant with global standards. These transformers aren’t just components—they’re engineered assets optimized for long-term reliability and metering precision.
Looking for custom-engineered, standards-compliant Toroidal Current Transformers? Contact Frigate for a quote, technical consultation, or sample request today.