numat / brooks-mfc

Python driver for Brooks Instrument Mass Flow Controllers

brooks-mfc

Python driver and command-line tool for Brooks Instrument mass flow controllers.

Installation

pip install brooks-mfc

Usage

This driver uses an undocumented REST API in the devices's web interface for communication. The compatibility and stability of this interface with all Brooks controllers is not guaranteed.

Command Line

To test your connection and stream real-time data, use the command-line interface. You can read the flow rate with:

$ brooks-mfc 192.168.1.200
{
    "Customer Flow Totalizer": 0.0,
    "Flow": -0.3,
    "Flow Hours": 1.0,
    "Flow Totalizer": 0.0,
    "Live Setpoint": 0.0,
    "Operational Hours": 50.0,
    "Setpoint": 0.0,
    "Supply Voltage": 22.93,
    "Temperature": 27.11,
    "Valve Position": 0.0
}

Note the "Live Setpoint" is in the configured units (which could be percent of full scale or engineering units). "Setpoint" is always in % of full scale.

You can optionally specify a setpoint flow with the set flag: brooks-mfc 192.168.1.150 --set 7.5. The units of the setpoint and return are specified using the --units flag, or the currently configured units if no flag is passed. See brooks-mfc --help for more.

Python

This uses Python ≥3.5's async/await syntax to asynchronously communicate with the mass flow controller. For example:

import asyncio
from brooks_mfc import FlowController

async def get():
    async with FlowController('the-mfc-ip-address') as fc:
        print(await fc.get())

asyncio.run(get())

The API that matters is get, set. Optionally, units can be passed with either command. If no units are specified the existing units configured for the device are used.

>>> await fc.get()
>>> await fc.get('%')
{
    "Customer Flow Totalizer": 0.0,
    "Flow": -0.3,
    "Flow Hours": 1.0,
    "Flow Totalizer": 0.0,
    "Live Setpoint": 0.0,
    "Operational Hours": 50.0,
    "Setpoint": 0.0,
    "Supply Voltage": 22.93,
    "Temperature": 27.11,
    "Valve Position": 0.0
}

>>> await fc.set(10)
>>> await fc.set(10, 'SCCM')

There's much more that could be set or returned from the flow controllers but I haven't had a reason to flesh all the the options out. Feel free to submit an issue with requests or a PR.

brooks-mfc's Issues

[Safe State Flag]

Script works only after manuall logging with "Control" user and turning on Safe State Flag on. Otherwise there is now air flow.