This script can be used to controll the Bronkhorst Gas Flow Controllers

bronkhorst-propar_set_bronkhorst_massflow_controller.py

#!/usr/bin/env python3

"""
Script Name: bronkhorst-propar_set_bronkhorst_massflow_controller.py
Author: Stefan Herdy
Date: 13.12.2019
Description: 
This script can be used to controll the Bronkhorst Gas Flow Controllers

Usage: 
- Install the bronkhorst-propar package (pip install bronkhorst-propar)
- use the functions below to controll the gas flow
"""

import propar
import time


def MFCinit(node):
    
    el_flow = propar.instrument(node)
    return el_flow

def setGasFlow(percent, el_flow):
    # Connect to the local instrument, when no settings provided 
    # defaults to locally connected instrument (address=0x80, baudrate=38400)
    

    # The setpoint and measure parameters are available 
    # as properties, for ease of use.
    # el_flow.setpoint = 15000
    MES_MODE = 0
    el_flow.write(1, 4, propar.PP_TYPE_INT8, MES_MODE)
    
    SETPOINT_SLOPE = 0.5
    el_flow.write(1, 2, propar.PP_TYPE_INT16, SETPOINT_SLOPE)
    

    # The instruments are scaled from 0 to 32000
    fval = percent/100*32000
    t = el_flow.write(1, 1, propar.PP_TYPE_INT16, int(fval))
    # print(x)
    time.sleep(SETPOINT_SLOPE)


    # All parameters can be read using the process and parameter numbers,
    # as well as the parameters data type. 
    # read the parameter to double-check if mass flow is actually set
    set_param = el_flow.read(1, 1, propar.PP_TYPE_INT16)
    
    return set_param

if __name__ == "__main__":
    # We used Raspbian as OS for our project
    # Specify the instrument node adress according to your OS
    node = '/dev/ttyUSB0'
    MFCinit()
    set_param = setGasFlow(int(input('Enter Flow Value in %: ')))
    print('Gas Flow set to: ' + str(int(set_param/32000*100)) + ' %')