TIDUFK1 August   2026

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Terminology
    2. 1.2 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Low Signal Amplitude
      2. 2.2.2 Sensitivity to Noise
      3. 2.2.3 Integrator limitation
      4. 2.2.4 Effect of Artificial Loads
      5. 2.2.5 Stray Magnetic Field Interference
      6. 2.2.6 Crosstalk
      7. 2.2.7 Mechanical Limitations
      8. 2.2.8 Human Errors
    3. 2.3 Highlighted Products
      1. 2.3.1 TLV4387
      2. 2.3.2 ADS131M08
      3. 2.3.3 MSPM0G1506
      4. 2.3.4 ISO6731
      5. 2.3.5 TPS70933
      6. 2.3.6 TRS3232
      7. 2.3.7 CDC6CE
  9. 3System Design Theory
    1. 3.1 Rogowski Coil
    2. 3.2 Hardware Integrator
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
    2. 4.2 Software
    3. 4.3 Test Setup
      1. 4.3.1 Header Information
    4. 4.4 Getting Started
      1. 4.4.1 Software Installation
      2. 4.4.2 GUI Setup
        1. 4.4.2.1 Calibration
    5. 4.5 Test Results
      1. 4.5.1  Active Power Accuracy Measurements
      2. 4.5.2  Active Power Accuracy Measurements (PF≠1)
      3. 4.5.3  Reactive Power Accuracy Measurements
      4. 4.5.4  Reactive Power Accuracy Measurements (PF≠1)
      5. 4.5.5  Voltage Variation Accuracy Measurements
      6. 4.5.6  Frequency Variation Accuracy Measurements
      7. 4.5.7  Equality of Current Circuits Accuracy Measurements
      8. 4.5.8  Phase Reversal Accuracy Measurements
      9. 4.5.9  Temperature Variation Accuracy Measurements
      10. 4.5.10 Crosstalk Accuracy Measurements
      11. 4.5.11 Effect of External Magnetic Fields Accuracy Measurements
  11. 5Design and Documentation Support
    1. 5.1 Documentation Support
    2.     Trademarks
  12. 6About the Author

2.2.5 Stray Magnetic Field Interference

Issue: Since Rogowski is a di/dt current sensor, it detects the change in flux over time. If there is a stray magnetic field close to the meter, the meter will pick up the magnetic fields and cause inaccurate billing.

Cause: Rogowski coils are sensitive to stray magnetic fields primarily because they are air-core sensors that rely on detecting the magnetic flux derivative, lacking a high-permeability shielding core to reject external fields.

Workaround: To address this, a differential coil with interleaved return loops is required. When exposed to external magnetic fields, this configuration generates a common-mode signal, which is then canceled by the differential amplifier. This reference design covers the differential amplifier implementation in detail.