Eaton easyE4 Programmable Relay

The Eaton easyE4 is a compact programmable logic relay designed for small-scale automation applications that traditionally use discrete relays, timers, and counters. This basic module features 12 inputs (including 4 analog inputs) and 8 relay outputs, operating on a 24 V DC power supply. The easyE4 replaces complex wiring and multiple discrete components with a single programmable device that can be easily reconfigured through software. It is ideal for machine control, lighting control, HVAC, and conveyor systems where a full-sized PLC is not required.

Technical Specifications

The easyE4 basic module includes 12 digital inputs (24 V DC, sink/source configurable). Among these, 4 inputs can be configured as analog inputs (0-10 V, 0-20 mA, or 4-20 mA) for reading sensors such as temperature, pressure, or position. The module provides 8 relay outputs (2 A at 30 V DC / 0.5 A at 240 V AC). The power supply is 24 V DC. Communication: built-in RS485 port supporting Modbus RTU, easy-NET, and other protocols. Programming is performed using Eaton easySoft software (free download) which supports ladder diagram and function block diagram languages. Program memory capacity is sufficient for typical small automation tasks with hundreds of function blocks. The module includes a real-time clock for time-based and astronomical switching. An optional external memory card provides program backup, data logging, and recipe storage. Dimensions are DIN rail mountable (35 mm). The front panel includes an LCD display (backlit) with 4 function keys for manual operation, status display, and parameter adjustment.

Key Features

• 12 digital inputs (4 configurable as analog inputs: 0-10 V, 0-20 mA, 4-20 mA)

• 8 relay outputs (2 A DC / 0.5 A AC)

• 24 V DC supply voltage

• Integrated RS485 port for Modbus RTU or easy-NET networking

• Programming languages: ladder diagram and function block diagram

• Real-time clock with calendar

• LCD display and keypad for on-screen configuration

• Function blocks: logic, timing, counting, analog processing, PID

• Expandable with up to 3 digital or analog extension modules

• Supports 35 mm DIN rail mounting

• CE, UL, CSA certified

Analog Input Capabilities

Four of the 12 inputs can be configured as analog inputs, eliminating the need for a separate analog module for basic analog applications. Analog input ranges are selectable via software: 0-10 V (default), 0-20 mA, or 4-20 mA. Resolution is 10-bit (approx. 1024 steps). The analog input values can be scaled within the user program to represent engineering units (e.g., temperature, pressure). The analog inputs can be used for applications such as monitoring room temperature for HVAC control, reading potentiometer position for speed control, or measuring current signals from pressure transmitters. The remaining 8 inputs remain as digital inputs.

Programming and Software

The easyE4 is programmed using Eaton easySoft software (available as a free download from Eaton's website). The software provides a graphical interface for selecting and connecting function blocks. Pre-programmed function blocks include logic gates (AND, OR, NOT, XOR), timers (on-delay, off-delay, pulse), counters (up, down, up/down), analog comparators, mathematical functions (add, subtract, multiply, divide), and PID controllers. The software supports online monitoring and simulation. Programs can be transferred to the easyE4 via the RS485 programming interface or via an optional USB programming adapter. The built-in LCD display allows basic monitoring and parameter adjustment without a PC.

Communication and Networking

The RS485 port supports Modbus RTU protocol, allowing the easyE4 to act as a Modbus slave to a higher-level PLC or SCADA system, or as a Modbus master to read data from remote sensors and drives. The easy-NET protocol allows multiple easyE4 modules to be networked together to exchange data (up to 8 modules). This is useful for distributed automation where I/O is spread across several locations. The module can also be used with Eaton's easyRemote software for HMI functionality.

Applications

The easyE4 is suitable for replacing discrete relay panels and timer banks in a wide range of applications including: small conveyors (start/stop control), lighting control (time-switched and occupancy-based), HVAC fan and damper control, pump alternating control (lead/lag), packaging equipment (simple sequence control), and garage door control. The analog inputs allow the module to control PID loops for temperature regulation or pressure control in simple applications.

Installation and Wiring

The easyE4 mounts on a 35 mm DIN rail. Connect 24 V DC power to the L+ and M terminals. Wire input devices (pushbuttons, switches, sensors) to the input terminals. For analog inputs, use shielded twisted-pair cable and connect the shield to the M terminal. Wire output loads (contactors, lamps, small solenoids) to the relay output terminals. Each output is rated at 2 A DC, 0.5 A AC; for higher currents, use an external contactor. The RS485 communication terminals (A, B) are used for networking or Modbus. The module includes removable terminal blocks for easy wiring and replacement. After wiring, power on and verify the LCD display shows the main screen. Load or create the program using easySoft.

Environmental and Compliance

The easyE4 is CE, UL, and CSA certified. It is RoHS compliant. Operating temperature: 0°C to 55°C. Storage temperature: -25°C to 70°C. Humidity: 10-95% non-condensing. Protection rating: IP20 (must be installed in a control cabinet). Vibration resistance: 2g (10-55 Hz).

Conclusion

The Eaton easyE4 programmable relay combines 12 inputs (with 4 analog capable), 8 relay outputs, and flexible communication in a compact, low-cost device. It is an ideal solution for small automation tasks where the simplicity of a programmable relay meets the I/O needs without the complexity of a full PLC.