Pylogix Data Logger

This program uses the Pylogix library to monitor tags on connected Allen-Bradley PLCs and log the data to a csv file. It can trigger periodically or based on tag data.

Setup

1. Download & install Python if you haven't already. Make sure to add Python to path/environment variables during install.
2. Run 'setup.bat' (Windows) or 'setup.sh' (Unix) to install dependencies.

Usage

1. Connect to the same network as the PLC (you can ping to verify)
2. Open a terminal in the same directory as logger.py
3. Run python logger.py -c {path_to_config_file.json} -f {path_to_output_file.csv}

JSON Config

Field	Info
ip	Specify the IP address of the connected controller.
tags	List the PLC tags you want to log. Specify program name for program-scope tags.
headers	List headers for the output CSV file.
trigger_type	Options: "change", "periodic", "compare".
trigger_tag	When using "change" or "compare" trigger, specify the tag to monitor/compare.
period_time	When using "periodic" trigger, specify time in seconds between logs.
compare_condition	Specify when using "compare" trigger. Options: "grt", "geq", "les", "leq", "neq", "equ".
compare_cutoff	Value to compare the selected tag to.
print_timestamp	Enable (1) / Disable (0) timestamp field in output log.
live_update	Enable (1) / Disable (0) live output updates. Live updates show data immediately but reduce performance.

Example JSON config - comparison trigger:

{
    "ip": "10.240.10.102",
    "tags": [
        "AI_Z9_MB1_05_00",
        "AI_Z9_MB1_05_01",
        "AI_Z9_MB1_05_02",
        "AI_Z9_MB1_05_03"
    ],
    "headers": [
        "LRT1",
        "LRT2",
        "LRT3",
        "LRT4"
    ],
    "trigger_type": "compare",
    "trigger_tag": "AI_Z9_MB1_05_00",
    "period_time": 0,
    "compare_condition": "les",
    "compare_cutoff": 1866.5625,
    "print_timestamp": 1,
    "live_update": 0
}

Example JSON config - periodic trigger:

{
    "ip": "10.240.10.102",
    "tags": [
        "AI_Z9_MB1_05_00",
        "AI_Z9_MB1_05_01",
        "AI_Z9_MB1_05_02",
        "AI_Z9_MB1_05_03"
    ],
    "headers": [
        "LRT1",
        "LRT2",
        "LRT3",
        "LRT4"
    ],
    "trigger_type": "periodic",
    "trigger_tag": "",
    "period_time": 0.25,
    "compare_condition": "",
    "compare_cutoff": 0,
    "print_timestamp": 1,
    "live_update": 1
}

Example JSON config - program-scope tags:

{
    "ip": "10.240.10.102",
    "tags": [
        "Program:HMI.Trim_Banner_Title",
        "Program:HMI.Trim_Banner_Message"
    ],
    "headers": [
        "Title",
        "Message"
    ],
    "trigger_type": "change",
    "trigger_tag": "Program:HMI.Trim_Banner_Title",
    "period_time": 0,
    "compare_condition": "",
    "compare_cutoff": 0,
    "print_timestamp": 1,
    "live_update": 0
}

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Written by Ben DeWeerd.