Precision power analyzers measure current directly using internal or external shunts with high accuracy at lower current levels. At higher currents, shunt-based measurement becomes impractical due to heat, power loss, and safety limits, requiring fluxgate current sensors to safely and accurately scale current into the analyzer.
While many current-sensing technologies exist, including current transformers, Hall effect sensors, Rogowski coils, and external shunts, they lack the stability, linearity, and phase accuracy required for precision power analysis. Fluxgate current sensors are preferred because they provide:
- True AC and DC measurement
- Extremely low offset and temperature drift
- Excellent linearity and stable phase performance
Yokogawa fluxgate current sensors cover 50 A to 5000 A and support clamp-on or through-hole measurement. When paired with Yokogawa precision power analyzers, they deliver a complete, traceable solution for accurate high-current measurement in EV, renewable energy, power electronics, and advanced R&D applications.
| Model | Type (Technology) | Rated Current | Sensor Output | Bandwidth | Accuracy (DC, 50/60 Hz AC) |
|---|---|---|---|---|---|
| CT Series | Through hole (Fluxgate) | 60 Arms to 2000 Arms (3000 Apeak) | Amps | DC to 800 kHz | ±0.05% of rdg + 30 µA |
| DS Series | Through hole (Fluxgate) | 50 Arms to 600 Arms (900 Apeak) | Amps | DC to 1 MHz | 0.0004% of rdg + 0.00012% of FS |
| DM1200ID | Through hole (Fluxgate) | 1200 Arms (1500 Apeak) | Amps | DC to 400 kHz | 0.0004% of rdg + 0.00002% of FS |
| DL2000ID | Through hole (Fluxgate) | 2000 Arms (3000 Apeak) | Amps | DC to 300 kHz | 0.0002% of rdg + 0.00001% of FS |
| IT Series | Through hole (Fluxgate) | 60 Apeak to 1000 Apeak | Amps | DC to 150 kHz | 0.0003% of rdg + 0.025% of FS |
| IN Series | Through hole (Fluxgate) | ±1500 Apeak / ±3000 Apeak | Amps | DC to 440 kHz / 40 kHz | 0.0002% of rdg + 0.0006% of FS |
| ITZ Series | Through hole (Fluxgate) | ±2000 Apeak / ±5000 Apeak | Amps | DC to 80 kHz | 0.0003% of rdg + 0.0002% of FS |
| CT1000S | Clamp-on (Fluxgate) | 1000 Arms (1500 Apeak) | Volts | DC to 300 kHz | ±0.2% of rdg + 0.01% of FS |
To contrast precision current sensors, Yokogawa also offers current probes designed for use with oscilloscopes and ScopeCorder platforms. These probes are optimized for waveform visualization and troubleshooting, but they do not provide the accuracy, stability, or phase performance required for precision power analysis.
| Model | Type (Technology) | Rated Current | Sensor Output | Bandwidth | Accuracy (DC, 50/60 Hz AC) |
|---|---|---|---|---|---|
| 720931 | Clamp-on (Transformer) | 200 Arms | Volts | 40 Hz to 3.5 kHz | ±0.5% of rdg ±0.1 mV |
| 96001 | Clamp-on (Transformer) | 400 Arms (600 Apeak) | Volts | 20 Hz to 20 kHz | ±1.0% of rdg ±0.2 mV |
| 751552 | Clamp-on (Transformer) | 1000 Arms (1400 Apeak) | Amps | 30 Hz to 5 kHz | ±0.3% of rdg |
| 701931 | Clamp-on (Hall Effect) | ±500 Apeak | Volts | DC to 10 MHz | ±2% of rdg |
In some power measurement applications, the current in the device under test is higher than what can be applied directly to the power analyzer current input terminals. Current transformers are used to step down high AC and DC currents to a lower level that can be measured directly by the power analyzer. These systems safely step down currents while preserving the highest accuracy.
Industry leading high precision, high current AC/DC split core measurement. Compatible with power analyzers and waveform measurement instruments.
- Closed-loop, fluxgate-based measurement for DC and AC power analysis
- Continuous current ratings from 50 amps up to 600 amps
- Wide bandwidth up to 1 MHz
- Exceptional accuracy with extremely low offset, ppm-level linearity, and excellent stability
- Closed-loop, fluxgate-based measurement for DC and AC power analysis
- Continuous current rating to 1500 amps
- Wide bandwidth up to 400 kHz
- Exceptional accuracy with extremely low offset, ppm-level linearity, and excellent stability
- Closed-loop, fluxgate-based measurement for DC and AC power analysis
- Continuous current rating up to 3000 amps
- Wide bandwidth up to 300 kHz
- Exceptional accuracy with extremely low offset, ppm-level linearity, and excellent stability
- Closed-loop, zero-flux measurement for high-accuracy DC and AC current sensing
- Wide current range from tens of amps up to 1000 A continuous, supporting precision lab and power electronics testing
- Wide bandwidth with low noise for accurate steady-state and dynamic measurements
- Excellent linearity and low offset, delivering stable, repeatable results over time and temperature
- Closed-loop, zero-flux measurement for DC and AC power analysis
- Up to 1500 A peak and 3000 A peak maximum current capability
- Wide bandwidth up to 2.5 MHz
- Excellent accuracy with low offset, high linearity, and long-term stability
- Closed-loop, fluxgate-based measurement for high-accuracy DC and AC power analysis
- Nominal current classes of 2000 A and 5000 A for very high-current test applications
- Wide bandwidth suitable for dynamic measurements at 50/60 Hz and higher frequencies
- Ppm-level linearity with extremely low offset and excellent long-term stability
600 Amp Peak Programmable Current Transformer System consisting of a 19 inch Rack Mount Power Supply/Signal unit, one CT Head, 5-Meter Signal Cable and 10-Meter Connecting Cable.
In this application note you will learn when and how to use different methods to connect a current transformer to a power analyzer.
