The ESP32 PLC 14 is a compact industrial PLC built for distributed control — reliable connectivity, open-source programming, and room to grow.
Small footprint. Real industrial work.
Not every automation task needs a large controller. Many of the most common jobs at the field level — reading sensors, controlling outputs, sending data to a central system, bridging two protocols — happen close to the equipment.
For this kind of work, a large PLC is too much. A bare microcontroller is not enough.
The ESP32 PLC 14 is designed for exactly this space: a compact, DIN-rail mounted industrial PLC with real I/O, a full set of communication options, and no licensing fees. It handles the control and monitoring tasks at the field level, and connects them to the rest of your system — whatever that system looks like.
Two processors, doing two things at once
Inside the ESP32 PLC 14, two independent processor cores run in parallel. One manages I/O and control logic. The other handles communications.
This matters in practice. In controllers with a single processor, I/O and network tasks share the same resources. When one is busy, the other waits. In time-sensitive industrial applications, that wait creates problems.
With two cores working independently, the ESP32 PLC 14 can read inputs and run control logic at the same time as it sends data over Modbus, MQTT, or any other protocol — without one affecting the other.
14 I/Os — and space to expand
The base unit provides 14 I/Os:
- 2 analog inputs 0–10V / 4–20mA
- 2 analog inputs 0–10V (also configurable as digital inputs)
- 3 digital inputs 3.3–24Vdc
- 4 digital outputs 12/24Vdc (also configurable as digital inputs)
- 1 relay output (48Vdc / 220VAC)
For applications that grow beyond this, the I2C expansion architecture supports up to 127 additional modules — scaling to more than 7,000 I/Os in a master-slave configuration. The base unit stays in place; the system grows around it.
Communication built for industrial environments
The ESP32 PLC 14 includes the connectivity options that cover most industrial and IIoT applications:
- Ethernet — stable wired network connection
- WiFi — for sites where cabling is not practical
- Bluetooth BLE — local configuration or mobile access
- RS485 — Modbus RTU, the protocol used by most industrial sensors and drives
When a project needs cellular or long-range wireless, expansion modules add NB-IoT, GPRS, 2G/3G/4G, and LoRa — without replacing the base unit.
Remote firmware updates over Ethernet are also supported. Configuration changes and software updates on deployed units do not require a visit to the site. For installations across multiple locations, this reduces maintenance time and cost over the life of the system.
Open-source programming. No licensing fees.
The ESP32 PLC 14 is programmed with Arduino IDE — a free, open-source development environment with a large library ecosystem covering Modbus, MQTT, OPC-UA, HTTP, and most protocols used in industrial applications.
There are no seat licenses, no annual renewals, and no dependency on a single vendor's toolchain. Engineers already familiar with Arduino-based development can start immediately. Engineers coming from other backgrounds will find extensive documentation and community support.
CORE or FLEX
ESP32 PLC 14 CORE — complete and ready to deploy. Everything integrated, one part number.
ESP32 PLC 14 FLEX — choose the communication expansion modules your application requires. Build only what the project needs.
→ ESP32 PLC 14 FLEX — configure yours
What it is good for
Distributed monitoring and control — deploy multiple units across a facility, each handling local I/O and reporting to a central system.
Protocol bridging — connect legacy field devices running Modbus RTU to modern IIoT platforms over Ethernet or cellular.
OEM integration — embed a compact, fully connected industrial controller into your own equipment, with a development environment your team already knows.
Edge nodes in larger systems — use the ESP32 PLC 14 as a field-level node feeding data to a higher-level controller or cloud platform.
In short
- Compact DIN-rail industrial PLC
- Dual-core processor: I/O and communications run independently
- 14 I/Os, expandable to 7,000+ via I2C modules
- Ethernet, WiFi, BLE, RS485 — plus cellular and LoRa expansion
- Remote firmware updates over Ethernet
- Open-source programming, no licensing fees
- CORE (ready to deploy) and FLEX (configure to spec)
→ Explore the full ESP32 PLC range at industrialshields.com
A small controller with a serious job to do