Phase Angle Voltmeter - 2251

Model Instrument 2251

Phase Angle Voltmeter - 2251

NAIs 2251 Phase Angle Voltmeter is one of the most versatile AC Measurement Instruments available. It employs a microprocessor-based design utilizing Fast-Fourier Transform techniques that combine many of the capabilities of today's network/waveform analyzers in a Digital Analyzing Voltmeter configuration. Like the 2250, the 2251 incorporates the most commonly used functions, providing a more cost-effective measurement instrument with fewer features and reduced accuracy requirements.

The 2251 is exceptionally “user friendly.” Simply pressing individual switches on the front panel enables the 2251 to make highly accurate ratio measurements in both phase-sensitive and voltage modes; measure percent, total harmonic distortion, and the magnitude and phase of selected harmonic; and compute the percent deviation of a signal from a selected nominal. Isolated inputs allow null, ratio, and gain measurements of key parameters. Specifically designed for the Synchro/Resolver and LVDT/RVDT marketplace, the 2251 is ideally suited for defense, industrial, and commercial applications.

This product is Obsolete. View our Obsolescence Policy for additional information. Please refer to model 2250A for details on the closest replacement product.



  • ± 0.05 % phase angle and ratio accuracy
  • 30 Hz to 54 kHz frequency response
  • Full feature display
  • IEEE interface standard
  • Voltage resolution 4 1/2 digits
  • Phase angle resolution 0.01°
  • 3-digit frequency display resolution
  • Self-calibrating
  • Multifunction
  • High accuracy
  • Replacement for obsolete models 212, 213, 214, & 321
  • Rack-mount or bench-top installation
  • 6-inch bi-polar nullmeter


Document DownloadsDate
2251 Specifications
Software DownloadsDate
2251 Labview Driver