Rogowski Coils and Current Transformers

Rogowski coil advantages:

• Measures over a very wide current range with a single coil
• Wider bandwidth for high and low frequencies
• Lower harmonic distortion
• Does not load the circuit
• Will not saturate if a DC component is present
• No danger from open-circuit secondary
• Better transient response
• Compact and lightweight especially for measuring very large currents
• Not damaged by large overloads
• Can be made in a 'split' version without sacrificing accuracy or phase integrity

Current Transformer Advantages:

• Well-established technology
• Cheaper for some low-current applications
• Does not require a power supply

Rogowski Coils and Hall-effect Transducers

Rogowski coil advantages:

• Measures over a very wide current range with a single coil
• Withstands large sustained overloads without damage
• Does not load the circuit being measured
• Transducer output is less noisy
• Lower power consumption
• More compact especially for large conductors and large currents

Hall-Effect Transducer Advantages:

• Measures down to DC

Rogowski Coils and Resistive Shunts

Rogowski coil advantages:

• No direct electrical contact with the conductor
• Much more compact for high current measurements
• Easy to calibrate accurately for very large currents
• Does not heat up
• Can withstand large overloads without damage and with rapid recovery
• Does not load the circuit
• Installation does not need modification to the busbars

Resistive Shunt Advantages:

• Measures down to DC
• Better for low-current measurements