Version 2.004.008 of the PA4000 firmware has the following changes implemented:

Enhancements
1. Instrument configurations can now be saved and recalled to a USB memory device.
2. The interval at which results are logged to a USB memory device can now be set.
3. Communication commands have been added to be able query the state of a number of instrument settings. Commands were added to support new functionality. Examples include:
  a. Wiring type query command.
  b. Harmonics setup query commands.
  c. Distortion setup query commands.
  d. Integrator setup query commands.
  e. Data out logging interval set and query.
  f. Data out logging status query.
  g. Set and Query of the Analog range. Set Analog range is duplicate of existing command that has the same function.
4. Auxiliary results are now paused when HOLD is pressed. 

Minor Changes
1. Fixed the communication results returned when a math formula produces an INVALID value. 
2. Improved the robustness of USB client communications. 
3. Improved the External frequency Counter to deal with signals that are modulated. 
4. Saving to USB memory has been improved to avoid the loss of data if the memory device is removed without stopping logging.
5. Fixed the issue of incomplete data records in the USB results file that can occur after data logging to USB is turned off. 
6. A USB Flash drive and USB communications conflict has been resolved.
7. Changed the VAR result unit to VAr.
8. Fixed a display issue that caused waveforms to look as if there was a DC offset.