Yokogawa WT1801E Precision Power Analyzer

The Yokogawa WT1801E is a single-channel precision power analyzer engineered for high-accuracy AC and DC power measurement across power supplies, inverters, and power electronic devices. It delivers simultaneous voltage, current, and power acquisition with 16-bit resolution at 2 MHz sampling rate, enabling detailed characterization of fast transients and harmonic content. The instrument performs harmonic analysis to the 500th order at 50/60 Hz fundamentals with update intervals as low as 50 milliseconds, and measures distortion factors including THD, fundamental, and individual harmonic components.

Energy quantification extends to grid-tied and battery-coupled applications, capturing energy bought/sold or charged/discharged. Motor testing is supported through analog and pulse sensor inputs for simultaneous rotation speed, torque, and mechanical power acquisition. High-speed data capture delivers Sigma-Urms, Sigma-Irms, and Sigma-P measurements every 5 ms from DC signals and three-phase devices.

Technical Specifications

• Harmonic analysis to 500th order at 50/60 Hz fundamental


• Data update interval: 50 milliseconds minimum


• Basic power accuracy: 0.05% of reading ± 0.05% of range


• Frequency range: DC to 1 MHz


• Sampling rate: 2 MHz with 16-bit resolution


• Minimum frequency for harmonic measurement: 0.1 Hz (without external sampling clock)


• High-speed capture interval: 5 milliseconds (Sigma parameters from DC and three-phase)


• Measurement intervals: manual or automatic


• Voltage input: 1.5 V to 1000 V (direct connection)


• Current input: 10 mA to 5 A or 1 A to 50 A (selectable elements)

Key Features

• Single input channel configuration


• Motor power analysis via analog and pulse sensor inputs


• Energy measurement for grid and battery systems


• Simultaneous THD, fundamental, and harmonic component measurement


• Motor speed, torque, and mechanical output characterization


• Configurable measurement intervals

Connectivity & Integration

• PC connectivity with Ethernet communication


• Remote screen display and instrument control via PC


• Web server functionality for remote operation and monitoring


• Modbus and Ethernet interface options available

Typical Applications

• Power supply and inverter evaluation


• Harmonic distortion analysis in industrial equipment


• Motor efficiency and mechanical power measurement


• Grid-connected renewable energy systems


• Battery charging and discharge characterization