The Medusa Power Analyzer PLUS is a unidirectional DC power meter with LCD display and RS-232 serial output. It ships with a Windows GUI app that records and plots.
But here's a simple command line tool that reads the raw data and logs averages to a file.
With no arguments it simply logs data from COM1 and prints averages every 10 seconds.
C:\tvb> compap port=1 seconds=10 stamp=0 limit=0 debug=0 ** Opening port \\.\COM1 (19200 baud) ** Opening file pap18437.txt ** Receiving good data... 48.10 V 0.990 A 16.1976 Ah 47.6 W 778.66 Wh 48.09 V 0.994 A 16.1998 Ah 48.0 W 778.76 Wh 48.09 V 0.993 A 16.2025 Ah 47.9 W 778.89 Wh ** Closing pap18437.txt |
Command line arguments are:
Averages are displayed modulo the number of seconds specified. For example, 60 second averages are displayed at the top of the minute (according to PC time); 10 second averages every multiple of 10 seconds, etc. An average time of 0 means display raw data from the Medusa (at a rate of approximately 320 ms per sample).
Time stamp options are any binary combination of:
Each run produces a new log file in the current directory with name pap#.txt with incrementing log number.
Here is an example using COM1, 5 second averages, UTC time stamps, for a maximum of 10 lines of output:
C:\tvb> compap 1 5 4 10 port=1 seconds=5 stamp=4 limit=10 debug=0 ** Opening port \\.\COM1 (19200 baud) ** Opening file pap18441.txt ** Receiving good data... 2005-04-08 00:28:05 48.09 V 1.003 A 16.3186 Ah 48.3 W 784.50 Wh 2005-04-08 00:28:10 48.11 V 0.998 A 16.3195 Ah 48.1 W 784.58 Wh 2005-04-08 00:28:15 48.12 V 0.994 A 16.3209 Ah 48.1 W 784.63 Wh 2005-04-08 00:28:20 48.08 V 0.997 A 16.3223 Ah 48.1 W 784.70 Wh 2005-04-08 00:28:25 48.09 V 0.996 A 16.3236 Ah 48.1 W 784.78 Wh 2005-04-08 00:28:30 48.11 V 0.994 A 16.3251 Ah 48.1 W 784.83 Wh 2005-04-08 00:28:35 48.10 V 1.000 A 16.3265 Ah 48.3 W 784.90 Wh 2005-04-08 00:28:40 48.09 V 0.993 A 16.3277 Ah 48.0 W 784.99 Wh 2005-04-08 00:28:45 48.10 V 0.998 A 16.3293 Ah 48.2 W 785.03 Wh 2005-04-08 00:28:50 48.11 V 0.996 A 16.3306 Ah 48.2 W 785.10 Wh ** Closing pap18441.txt |
This example produces 5 one minute averages with MJD time stamps.
C:\tvb> compap 1 60 2 5 port=1 seconds=60 stamp=2 limit=5 debug=0 ** Opening port \\.\COM1 (19200 baud) ** Opening file pap18442.txt ** Receiving good data... 53468.022917 48.10 V 0.997 A 16.3976 Ah 48.1 W 788.36 Wh 53468.023611 48.10 V 0.997 A 16.4089 Ah 48.1 W 788.90 Wh 53468.024306 48.10 V 0.996 A 16.4255 Ah 48.0 W 789.71 Wh 53468.025000 48.10 V 0.998 A 16.4421 Ah 48.1 W 790.51 Wh 53468.025694 48.10 V 0.996 A 16.4585 Ah 48.0 W 791.31 Wh ** Closing pap18442.txt |