ESP32 PLC: industrial controller based on the ESP32
An ESP32 PLC is a programmable logic controller built around the ESP32 chip from Espressif and packaged for industrial use: DIN-rail mounting, a 12 to 24 Vdc supply and industrial inputs and outputs. The Industrial Shields ESP32 PLC family adds Ethernet, Wi-Fi, Bluetooth LE and RS-485, and you program it with the Arduino IDE.
8 models, from 9 inputs and 5 outputs to 37 inputs and 24 outputs · Optional LoRa or 4G board · Programming over USB or Ethernet
Industrial applications of the ESP32 PLC by sector
Real installations documented as case studies, and simulators you can run in the browser.
Manufacturing and machines
Machine monitoring, OEE, retrofits of old lines, test stations and robot cells. The ESP32 PLC reads stops, counters and energy and sends them to MQTT, databases or BI tools.
Case studies- Knitting machine and energy monitoring
- Packaging line retrofit
- Bodegas Care bottling line
- Cobot cell for automotive parts
- Electronic board testing
Logistics and material handling
Pneumatic gates, pick and pack stations, traceability and auxiliary I/O on mobile robots, with commands that come from a database or an ERP.
Case studies- Pneumatic gate control from MySQL
- Packaging line traceability
- E-commerce pick and pack
- AGV auxiliary I/O and safety status
Water, energy and utilities
Dosing, water metering, oil wells, fluid storage, boilers and solar plants. Typical links are Modbus TCP to a SCADA, 4G for remote sites and a local SD card backup.
Case studies- Water treatment: pH and chlorine dosing
- FEDA water consumption monitoring
- Oil well remote monitoring over 4G
- Fluid transport and storage monitoring
- Steam boiler automation
- Solar tracker data gateway
Agriculture
Irrigation by sectors and greenhouse climate, with alarms and remote control from a phone.
Case studiesSimulatorsTransport and mobile equipment
Control and data logging on board, with 4G LTE-M when there is coverage and local storage when there is not.
Case studiesBuildings, access and smart city
Access gates on Wi-Fi, people and vehicle counting, alarms to Telegram, order systems and street equipment.
Case studies- Gate access control on Wi-Fi
- Solar compacting litter bin
- Petrol station traffic monitoring
- Hospital room alarm with Telegram
- Restaurant order system
Gate access control with an ESP32 PLC at a game reserve. Read the case study.
ESP32 PLC models, inputs, outputs and communications
All models mount on a DIN rail, run on 12 to 24 Vdc, have an IP20 enclosure and are programmed with the Arduino IDE over USB or Ethernet.
| Model | Inputs | Outputs | Built-in communications | Optional board |
|---|---|---|---|---|
| ESP32 PLC 14 | Inputs9 (2 analog/digital) | Outputs5 (1 relay) | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, I2C | Optional boardLoRa, 4G |
| ESP32 PLC 19R | InputsSee product page | OutputsSee product page | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, RS-232, I2C, SPI | Optional boardLoRa, 4G, CAN |
| ESP32 PLC 21 | Inputs13 (6 analog/digital) | Outputs8 (3 PWM/analog) | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, RS-232, I2C, SPI | Optional boardLoRa, 4G, CAN |
| ESP32 PLC 38AR | Inputs19 (10 analog/digital) | Outputs19 (8 relays, 6 PWM/analog) | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, RS-232, I2C, SPI | Optional boardLoRa, 4G, CAN |
| ESP32 PLC 38R | Inputs12 (8 analog/digital) | Outputs22 (16 relays, 6 PWM/analog) | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, RS-232, I2C, SPI | Optional boardLoRa, 4G, CAN |
| ESP32 PLC 42 | Inputs26 (12 analog/digital) | Outputs16 (6 PWM/analog) | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, RS-232, I2C, SPI | Optional boardLoRa, 4G, CAN |
| ESP32 PLC 57R | Inputs18 (12 analog/digital) | Outputs33 (24 relays, 9 PWM/analog) | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, RS-232, I2C, SPI | Optional boardLoRa, 4G, CAN |
| ESP32 PLC 58 | Inputs37 (16 analog/digital) | Outputs24 (9 PWM/analog) | Built-in communicationsEthernet, Wi-Fi, Bluetooth LE, RS-485, RS-232, I2C, SPI | Optional boardLoRa, 4G, CAN |
The ESP32 PLC 14 and 21 come in CORE and FLEX versions. Data from each product page; check the datasheet on the product page before you wire the controller. See all ESP32 PLC models in the shop.
Ethernet, Wi-Fi, Bluetooth, RS-485 and 4G on the ESP32 PLC
- EthernetEvery model has an Ethernet port for Modbus TCP, MQTT or HTTP, and for programming over the network.
- Ethernet guideEthernet connection with an ESP32 PLC
- Wi-Fi and Bluetooth LEBuilt into the ESP32. Wi-Fi connects machines where there is no cable; Bluetooth LE lets a phone act as the operator panel.
- Wi-Fi and Bluetooth guideESP32 PLC Wi-Fi, Bluetooth and BLE guide
- RS-485 and RS-232RS-485 on every model for Modbus RTU with meters, drives and sensors. RS-232 on all models except the ESP32 PLC 14.
- RS-485 guideRS-485 with Arduino and ESP32 based PLCs
- 4G and LoRaOptional communication board for remote sites without cable or Wi-Fi. 4G sends data straight to the cloud; LoRa covers long distances with low power.
- 4G guideHow to use 4G with the ESP32 PLC
Why choose an ESP32 based PLC
- Dual core. One core can run the I/O logic while the other handles communications.
- No license fees. You program it with free software such as the Arduino IDE.
- Modular. Choose the model by number of inputs and outputs, and add I2C expansion modules when the project grows.
- Secure. You write and control the firmware, so you decide the security layers of your solution.
- Support. Our engineers help you from the first contact to after-sales.
Programming the ESP32 PLC
You program the ESP32 PLC with the Arduino IDE over USB or Ethernet. Ready-to-use code for 4-20 mA sensors, Modbus, MQTT and other functions is in the PLC Solution Library, and complete projects with ESP32 PLC are in the PLC project packs.
Frequently asked questions about the ESP32 PLC
What is an ESP32 PLC?
An ESP32 PLC is a programmable logic controller built around the ESP32 chip from Espressif and packaged for industrial use: DIN-rail mounting, a 12 to 24 Vdc supply and industrial inputs and outputs. The Industrial Shields ESP32 PLC adds Ethernet, Wi-Fi, Bluetooth LE and RS-485, and you program it with the Arduino IDE.
What is the ESP32 used for in industrial automation?
In Industrial Shields case studies the ESP32 PLC monitors machines and energy, controls gates, dosing and boilers, runs irrigation, logs data on trains and remote sites over 4G, and handles access, counting and alarms in buildings.
Which communications does the ESP32 PLC have?
All models have Ethernet, Wi-Fi, Bluetooth LE, RS-485 and I2C. All models except the ESP32 PLC 14 also have RS-232 and SPI. An optional board adds LoRa or 4G, and CAN on the models that list it.
Does the ESP32 PLC have Ethernet?
Yes. Every ESP32 PLC model has an Ethernet port, and you can also program the controller over Ethernet.
Can I add a 4G module to an ESP32 PLC?
Yes. 4G is available as an optional communication board; the product page of each model lists its options. It is used in the railway, oil well and pivot irrigation case studies on this page.
How do you program an ESP32 PLC?
With the Arduino IDE, over USB or Ethernet. Industrial Shields also publishes a guide to use the ESP32 PLC with OpenPLC.
What power supply does the ESP32 PLC need?
12 to 24 Vdc. The controller mounts on a DIN rail and has an IP20 enclosure.
Which ESP32 PLC model should I choose?
Count the inputs and outputs you need, with a margin for changes, and check how many must be analog or relay. Then pick the smallest model in the table that covers them. If you are not sure, send us your signal list with the form on this page.
- Count the inputs and outputs you need.
- Add a margin for changes.
- Check how many must be analog or relay.
- Pick the smallest model in the table that covers them.
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