The RoCon RFI 421 is a versatile industrial programmable logic controller (PLC) built for robust automation tasks. With four analog inputs, four digital inputs, and four relay outputs, it enables reliable control and monitoring of process systems. It supports serial communication via RS-232 and RS-485 and is powered by a wide input range of 24–110 VDC. The integrated keypad and LCD panel offer direct front-panel programming and status feedback, making it ideal for standalone or distributed automation setups.

Key Features:

Model: RFI 421 (Type 5A)
Brand: RoCon PLC
Power Supply: 24–110 VDC, 5.6 W
Analog Inputs: 4 channels (AI1–AI4), configurable for different sensor ranges
Digital Inputs: 4 isolated inputs (IN1–IN4)
Relay Outputs: 4 digital relay outputs (OUT1–OUT4), typically rated for 230 VAC, 3 A
Communication: RS-232 and RS-485 ports for remote connectivity
User Interface:
- Front panel with tactile buttons
- 7-segment or small-character LCD display
- Status LEDs for READY, ST1–ST5
Mounting: Panel-mounted (IP52 from front panel)
Certifications: CE marked; made in Bulgaria

RoCon – RFI 421 – Industrial Control PLC, 24–110 VDC Input, RS232/RS485

RoCon – RFI 421 – Industrial Control PLC, 24–110 VDC Input, RS232/RS485