dr-files 0.1.2

Read and convert Mechbase files (.dr) to known file formats

DR Files

Read and convert MECHBASE files (.dr) to known file formats

MECHBASE

MECHBASE® is a complete preventive solution that was developed by Arpedon, P.C., in order to help you store and trend your equipment status.

MECHBASE files format

MECHBASE files have the following structure:

• 2 bytes - the size of the header in bytes, in little-endian short integer format
• next N bytes - the header, in this protobuf format
• remaining bytes - the values of the signals, with each value represented in 2 bytes, like below (signal has 3 channels in this example):
  • next 2 bytes - first value of the first channel, in little-endian short integer format
  • next 2 bytes - first value of the second channel, in little-endian short integer format
  • next 2 bytes - first value of the third channel, in little-endian short integer format
  • next 2 bytes - second value of the first channel, in little-endian short integer format
  • next 2 bytes - second value of the second channel, in little-endian short integer format
  • next 2 bytes - second value of the third channel, in little-endian short integer format
  • ...

Converting values to actual measured values

• divide the value by the maximum short value (32767)
• multiply the value with the channel reference value
• add the channel offset to the value
• multiply the value with 1000 and divide by the channel sensitivity value
• if channel db_reference exists and is positive
  • multiply the log10 of the absolute value divided by the db_reference with 20 - 20 * log10(abs(value) / db_reference)
  • add the channel pregain to the value

Reference code can be found in the value_converter function.