Ocean Controls KTA-223 Relayduino USB/RS-485 IO Module 12 VDC

The KTA-223 is a USB or RS-485 controlled IO module for interfacing PCs to real world applications, such as controlling lights and sprinkler systems, reading sensors and monitoring switches and other digital signals. It’s also an Arduino compatible controller and can be programmed with Arduino IDE for stand-alone operation.

The relays are capable of switching up to 10 A at 250 VAC (though see notes about PCB track heating in the manual). Optically-isolated digital inputs can be wired to NPN, PNP or dry contact (switch) type sensors. Three analog inputs can be used for 0 to 5 VDC or 0 to 20 mA (including industry standard 4 to 20 mA) signals.

A simple ASCII protocol allows control from Windows/Mac/Linux using either USB Virtual serial port drivers or RS-485. Additionally, multiple devices can be connected to one RS-485 bus, allowing control of many devices from one USB port.

Multiple controllers can be connected to one or more PCs in an RS-485 network. Each controller can be assigned an address and will respond to commands addressed to them.

The controller is based on the hardware of the Arduino physical computing controllers. It can be programmed as a stand-alone controller using the free, open source Arduino environment. Internally, the controller is “shield compatible”, allowing the use of many extension boards designed for the Arduino Deumilanove or Uno.

Features:

• 8 relay outputs 10 A, 250 VAC
• 4 Opto-isolated inputs 5 to 30 VDC
• 3 Analog inputs (10 bit), jumper selectable for 0 to 5 VDC or 0 to 20 mA
• Connections via pluggable screw terminals
• Power Indicator, TX and RX LEDs
• All enclosed in professional looking plastic case
• Arduino compatible
• Accepts Arduino shields (Ethernet / XBee)
• Communicates via USB (virtual serial port) or RS-485
• Easily connect multiple units far apart by RS-485
• Dimensions: 11 cm (L) x 14 cm (W) x 3 cm (H)

An example program has been written in both Visual Basic 6 and VB .Net to show you how to interface with the KTA-223 using a PC.

New in Version 9:

In June, we started shipping version 9 of the KTA-223. It’s fully compatible with the previous versions, but has a range of new features including:

• New relays with a higher contact to coil isolation voltage for safer switching of loads
• TX and RX LEDs visible from the outside fo the box
• Redesigned serial and USB circuitry and layout for higher baudrates, better reliability and better noise immunity
• The addition of a separate 3.3 VDC regulator to take the load off the FT232RL chip
• Changes to the layout inside to match the changes made with the Arduino Uno.

More detail can be found in the manual.

Resources:

• Download Manual (PDF)
• Download Schematic (PDF)
• Download Eagle Files
• Download Arduino Sketch
• SoftI2cMaster Arduino Library by William Greiman (for use with SFC-010, requires SCL_PIN to be 13 and SDA_PIN to be 12)
• VB2K8 Test Software & Source
• VB6 Test Software & Source
• Delphi Light Flasher Software & Source
• Time-A-Relay software (19th May 2011)
• Time-Clock software (5th Dec 2010)
• Web Interface Sketch (requires ethernet shield)
• Wifi Interface Sketch (requires WiFly shield – tutorial available; see link above)