What is the difference between high accuracy and low latency operation modes on the microPMU?

High Accuracy

  • Uses a filter implemented by Powerside that is longer than P and M class PMU filters.
  • The longer filter provides greater phasor measurement accuracy at the cost of increased data transfer latency (3-5 seconds) of its IEEE C37.118 service.
  • Only L1, L2, and L3 voltage and current phasors (magnitude/angle) are provided.
  •  Includes additional data interface separate from C37.118 that records phasor measurements into binary files on its local storage disk.
  •  FTP server can be enabled for access to recorded binary files.
  • User configurable data frame rate for C37.118 service.
  • The transfer protocol for the C37.118 service is user configurable between TCP or UDP (no mixed mode).

 Low Latency

  • No binary file recording or FTP service. Just a C37.118 service.
  • Provides user configurable choice between P and M class PMU filters on individual measurement input channels.
  • Provides phasor measurements for L1, L2 and L3 voltage currents.
  • Also provides phasor measurements on N-E voltage and I4-I14 current inputs (I9-I14 hardware inputs available only with add on current board).
  • Magnitudes for AN-E inputs (no angles) are provided as well.
  • C37.118 data frame rate locked to 120FPS@60Hz and 100FPS@50Hz.
  • Typical data transfer latency of about 50ms.
  • The transfer protocol for the C37.118 service is user configurable between TCP or UDP (no mixed mode).