~derf / projects / dlog-viewer
dark mode

dlog-viewer loads voltage, current, and/or power measurements from .dlog files produced by devices such as the Keysight N6705B DC Power Analyzer. It is specifically meant for .dlog files that were written to a USB stick by the power analyzer itself, so no Keysight software is required for analyzing them.

Measurements can be exported to CSV or plotted on-screen via matplotlib. There is also support for changepoint detection to automatically identify changes in the observed device behaviour. This is meant to work around a lack of digital synchronization signals in the logged power traces.

This program is not affiliated with Keysight and has not been thoroughly tested, as I only have a singly type of power analyzer at hand. Use at your own risk.


Obtain a .dlog file e.g. by using the instrument's data logger feature. dlog-viewer options include:

  • plots showing voltage, current, or power over time (--plot),
  • simple statistics (--stat, --skip, --limit)
  • changepoint detectiong using the PELT algorithm (--pelt),
  • CSV export of raw measurements (--csv-export), and
  • JSON export of measurements and detected changepoints (--json-export).

See bin/dlog-viewer --help for details.


  • Python 3, numpy, matplotlib, xml.etree
  • Changepoint detection: python3-ruptures