> For the complete documentation index, see [llms.txt](https://docs.cybus.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cybus.io/2-4-2/guides/machine-connectivity/plcs-industrial-controllers.md).

# PLCs & Industrial Controllers

These guides describe how to read data from programmable logic controllers (PLCs) and industrial controllers and map it into an ISA-95 style MQTT topic hierarchy. The following guides are available:

| Guide                                                                                                                                                   | Connector                                                                 | Description                                                                |
| ------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------- | -------------------------------------------------------------------------- |
| [Siemens S7 Device](/2-4-2/guides/machine-connectivity/plcs-industrial-controllers/connecting-and-integrating-a-siemens-s7-device.md)                   | [S7](/2-4-2/connectors/shop-floor-connectors/siemens-simatic-s7.md)       | Integrate SIMATIC S7 PLCs for industrial data exchange.                    |
| [SIMATIC S7-1500 via S7+](/2-4-2/guides/machine-connectivity/plcs-industrial-controllers/connecting-a-simatic-s7-1500-via-s7-plus.md)                   | [S7+](/2-4-2/connectors/shop-floor-connectors/siemens-simatic-s7-plus.md) | Read data with symbolic addressing, including optimized data blocks.       |
| [Allen-Bradley ControlLogix PLC](/2-4-2/guides/machine-connectivity/plcs-industrial-controllers/connecting-an-allen-bradley-controllogix-plc.md)        | [EtherNet/IP](/2-4-2/connectors/shop-floor-connectors/ethernet-ip.md)     | Read controller and program tags from a ControlLogix PLC.                  |
| [Schneider Modicon M580 PLC](/2-4-2/guides/machine-connectivity/plcs-industrial-controllers/connecting-a-schneider-modicon-m580-plc.md)                 | [Modbus/TCP](/2-4-2/connectors/shop-floor-connectors/modbus-tcp.md)       | Read located variables from a Modicon M580 PLC.                            |
| [WAGO PFC200 Controller](/2-4-2/guides/machine-connectivity/plcs-industrial-controllers/connecting-a-wago-pfc200-controller.md)                         | [Modbus/TCP](/2-4-2/connectors/shop-floor-connectors/modbus-tcp.md)       | Map PLC variables to Modbus registers in CODESYS and read them.            |
| [Phoenix Contact PLCnext Controller](/2-4-2/guides/machine-connectivity/plcs-industrial-controllers/connecting-a-phoenix-contact-plcnext-controller.md) | [OPC UA](/2-4-2/connectors/shop-floor-connectors/opc-ua/opc-ua-client.md) | Read data through the built-in OPC UA server of the controller.            |
| [Beckhoff TwinCAT System](/2-4-2/guides/machine-connectivity/plcs-industrial-controllers/connecting-a-beckhoff-twincat-system.md)                       | [OPC UA](/2-4-2/connectors/shop-floor-connectors/opc-ua/opc-ua-client.md) | Read data from a TwinCAT 3 PLC through the TwinCAT OPC UA Server (TF6100). |


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