PythonEquipmentDrivers

The purpose of this module is to provide a collection of classes for controlling various electronics laboratory instruments. The library of supported devices is categorized into 8 sub-categories that are accessed as sub-modules:

• Voltage Sources (pythonequipmentdrivers.source)
• Electronic Loads (pythonequipmentdrivers.sink)
• Multimeters (pythonequipmentdrivers.multimeter)
• Oscilloscopes (pythonequipmentdrivers.oscilloscope)
• Function Generators (pythonequipmentdrivers.functiongenerator)
• Power Meters/Analyzers (pythonequipmentdrivers.powermeter)
• Network Analyzers (pythonequipmentdrivers.networkanalyzer)
• Temperature Controllers (pythonequipmentdrivers.temperaturecontroller)

Installation

This library utilizes the NI-VISA (or compatible) hardware drivers, this should be installed prior to using this libray. To install this module download or clone this repository and install using pip with pip install . or C:\\{path_to_python}\python.exe -m pip install . if multiple Python installations exist.

Additionally the package can be installed in development mode with the -e/--editable flag e.g pip install -e . More details on development mode can be found at https://setuptools.pypa.io/en/latest/userguide/development_mode.html

For additional help with installation help you can contact the module author Anna Giasson ([email protected])

Examples

To create a connection to an instrument supported by this library it's respective class needs to be instantiated with the address of the instrument you wish to control. For example, to control a Chroma 62012P voltage source on a GPIB interface at address 14:

import pythonequipmentdrivers as ped
source = ped.source.Chroma_62000P('GPIB0::14::INSTR')

With this instance, various features of the instrument can be access through its methods.

source.set_voltage(48)
print(source.measure_voltage())
# 47.98645785

PythonEquipmentDrivers comes with a built in utility for identifing (most) connected instruments if the addresses are not known.

import pythonequipmentdrivers as ped
ped.identify_visa_resources()

By instantiating multiple instruments simple tests can be scripted to automatically log data for a "device under test" (DUT) Here is an example test which measures the efficiency of a power converter over multiple operating points and logs the resulting data to file:

import pythonequipmentdrivers as ped
from time import sleep

# connect to equipment
source = ped.source.Chroma_62000P('GPIB0::14::INSTR')
v_in_meter = ped.multimeter.Keysight_34461A('USB0::0x2A8D::0x1301::MY59026778::INSTR')
v_out_meter = ped.multimeter.Keysight_34461A('USB0::0x2A8D::0x1301::MY59026586::INSTR')
sink = ped.sink.Chroma_63206A('GPIB0::3::INSTR')

# initialize
source.set_voltage(0)
source.off()
source.set_current(10)

sink.off()
sink.set_mode('CC')
sink.set_current(0)

v_in_meter.set_mode('VDC')
v_out_meter.set_mode('VDC')

# conditions to test
v_in_conditions = (40, 48, 54, 60)
i_out_conditions = range(0, 120+1, 10)
measure_delay = 0.5
cooldown_delay = 5
data_file_name = 'C:\\top_sneaky\\my_first_test.csv'

# run test
data = [['v_in_set', 'i_out_set', 'v_in', 'i_in', 'v_out', 'i_out', 'efficiency']]
source.on()
sink.on()
for v_in_set in v_in_conditions:
    source.set_voltage(v_in_set)
    for i_out_set in i_out_conditions:
        print(f'Testing V_in = {v_in_set} V, I_out = {i_out_set} A')
        sink.set_current(i_out_set)
        sleep(measure_delay)
        datum = [v_in_set,
                 i_out_set,
                 v_in_meter.measure_voltage(),
                 source.measure_current(),
                 v_out_meter.measure_voltage(),
                 sink.measure_current()]

        sink.set_current(0)

        # calculations
        eff = (datum[4]*datum[5])/(datum[2]*datum[3])
        # add to data
        datum.append(eff)
        data.append(datum)

        sleep(cooldown_delay) # cool down unit

# shutdown test setup
print('Test complete!')
source.set_voltage(0)
source.off()
sink.set_current(0)
sink.off()

# log data
with open(data_file_name, "w") as file:
    for row in data:
        print(*row, sep=',', end='\n')
print(f'data saved to: {data_file_name}')

See the examples folder within this repository for additional examples.

Contributing

The tox package is utilized to automate formatting and testing for this project. Getting started with tox couldn't be easier:

Install the tox python package using pip:

pip install tox or C:\\{path_to_python}\python.exe -m pip install tox

Then in the PythonEquipmentDrivers root directory run the tox command:

tox or C:\\{path_to_python}\python.exe -m tox

Currently automated tests are pretty limited but do still check that the package will install and can be imported without errors.