The Ocean Controls KTA-223 is an Arduino-compatible USB relay controller that bridges PCs and microcontrollers to real-world industrial and automation devices. It provides eight relay outputs, four opto-isolated digital inputs, and three analog inputs with jumper-selectable measurement ranges. Communication occurs via USB virtual serial port (FTDI232-based) or RS-485, supporting ASCII command protocols across Windows, Mac OS X, and Linux platforms. The module accepts Arduino shields and can be reprogrammed using the Arduino IDE, making it suitable for home automation, robotics, industrial control, and networked multi-unit deployments.
Technical Specifications
Relay Outputs
• 8 × SPDT relays
• Contact Rating: 5 A @ 250 VAC, 10 A @ 120 VAC, 10 A @ 24 VDC
• PCB trace current limit: ~5 A sustained operation
Digital Inputs
• 4 × Opto-isolated inputs
• Input Voltage Range: 0 to 30 VDC
• Activation Threshold: ≤ 2.5 VDC
Analog Inputs
• 3 × 10-bit resolution
• Jumper-selectable ranges: 0 to 5 VDC or 0 to 20 mA (includes 4-20 mA)
• Input impedance: ~500 kΩ (0-5 V mode), ~250 Ω (0-20 mA mode)
• Overvoltage protection: Rated to ~36 VDC
Communication
• USB: Virtual COM port via FTDI232
• RS-485: Serial interface with USB-to-RS-485 conversion capability
• Protocol: ASCII commands
• Baud Rate: 1200 to 115200 baud (default 9600, nonvolatile)
• Data Format: 8 bits, No Parity, 1 Stop bit
• Unit Addressing: 00 to 99 (00 = broadcast)
Power Supply
• Input: 6.5 to 36 VDC (24 VDC nominal)
• Consumption: ~200 mA (plus external 5 V draw)
• Auxiliary 5 V Output: 100 mA
• Reverse polarity protection included
Physical Characteristics
• Enclosure: Plastic case, DIN-rail mountable
• Connections: Pluggable screw terminals
• Status Indicators: Power, TX, RX, and relay status LEDs
• Operating Temperature: -20°C to 70°C
• Dimensions: 140 mm (L) × 110 mm (W) × 30 mm (H)
– Key Features
• Simple ASCII protocol for straightforward integration
• Multiple relay control commands (RON, ROF, ON, OF)
• Real-time relay and input status monitoring
• RS-485 networking for multi-unit systems
• Arduino IDE reprogrammability
• Shield compatibility for expanded I/O and connectivity
– Typical Applications
Home and building automation, robotics platforms, industrial equipment control, networked sensor monitoring, and custom embedded systems requiring PC or microcontroller-based relay switching and signal acquisition.
– Compatibility & Integration
Fully Arduino-compatible with shield socket support. Operates on Windows, Mac OS X, and Linux. Firmware updatable via Arduino IDE. Multiple units addressable and networked via RS-485 for scalable distributed control systems.
