Power Monitor, AC- or DC-Powered

Power Monitor, AC- or DC-Powered

Model Modules 109

Power Monitor, AC- or DC-Powered

NAI’s 109 is an AC- or DC-Powered Power Monitor used to monitor voltage, frequency, and phase characteristics of single- or three- phase power lines. This allows normal operation of system loads when the power-line characteristics are within predetermined limits.

The 109 monitor provides three separate control circuits and output relays indicating the condition of each line characteristic. It is ideally suited for rugged defense and industrial applications.


  • AC- or DC-powered
  • Operates at 50/60/400 Hz
  • Single- or three-phase
  • Voltage, frequency, or phase outputs
  • Accuracy ±1%
  • Hysteresis 1% maximum
  • Time delay (pick-up & drop-out) 250 ms to 10 seconds
  • Real-time outputs 15 VDC @ 15 mA
  • High reliability
  • Versatile design allows for many variations

Document DownloadsDate
Power Monitor Comparison Matrix
109 Specification