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National Control Devices, LLC

Ultra Low Cost Wired Relays

Ultra Low Cost Wired Relays

RS-232 Serial Relay Controller

Our RS-232 Relay Boards are fully E3C complaint, allowing up to 256 NCD devices to share a single RS-232 serial port.  Mix and match up to 256 devices in any combination.  Speak to each device individually or all devices at once.

To control the this Relay Controller,  simply connect a data and ground wire between the Relay Controller and computer or microcontroller. Provide +12 Volts DC to the board, and send ASCII character codes to control the relays.

Even a no-frills design deserves a high-quality driver stage, and that's exactly what we put on our Serial Relay Controllers.  Fast-reacting flyback diodes help shunt dangerous voltages away from the driver circuit.

Features include no-click startup, LED status lights, and E3C compliance.  Relays can be controlled at 9600 baud and the board is compatible with ANY computer or microcontroller capable of delivering RS-232 data.