Post by Lake Shore Jeff M on Dec 21, 2020 8:45:30 GMT -5
The example python scrip captures a DC measurement by sending the SCPI, FETCh DC? command and recording the resulting values. To capture the RMA or Peak-to-Peak values you would need to modify the script to remove the FETCh DC? command and replace it with the one or all of the following commands:
FETCh FREQ? - returns the dominate Frequency FETCh RMS? - returns the RMS value of the axis specified FETCh Peak - returns the peak-to-peak measurement of the axis specified
Please review section 4.5.2 in the Model F71 User Manual for information regarding the SCPI commands that can be used with the Teslameter
Please note that although we do provide drivers and example applications, Lake Shore does not provide individual application development support for Python or Lab View software
Which field values in particular are you looking to record? Since you're wanting to record frequency readings, you probably don't need to record those values more often than once per second. Are you also wanting to record RMS and DC offset?
The frequency and RMS requests are just: myTeslameter.get_frequency()
myTeslameter.get_rms_field() Maybe you could ask for one second of buffered data, then frequency, and RMS, then another second of buffered data? Keep looping through that until you have the amount of data you're looking for? As long as you can get the frequency and RMS data out of the instrument fast enough, you shouldn't loose any of the data being buffered. If you do notice you're not able to get the data out fast enough, you might extend the buffer to 100 ms intervals?
Just depends on what you're trying to capture I guess. Feel free to respond with more information about what you're doing and we can make other suggestions.
Glad to hear you're getting some use out of the python scripts we added to the teslameter.
Ryan Oliver Product Manager, Sensors and Instruments Lake Shore Cryotronics