Product Code: R81DPDTCN
Setup for the R81DPDTCN RS232 relay shown above using the optional QS12 Quick Start Kit. Simply Connect the Serial Interface to your Relay Controller, connect the Power and Serial Cable and start sending commands.

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| 8-Channel 1-Amp DPDT Relay Controller with RS-232 and Relay Interface | |
| Stock#: R81DPDTCNRS | $149.00 |
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N-Button creates up to 8 desktop widgets to control relays without any programming. Order Today with This Board for Only $29 |
| Stock#: N-Button Lite | $49.00 |

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Convenient Terminal Blocks for easy electronic connections
Quick Start Kit Available for Easy RS232 Connection
Highly Reliable Relay Board For Demanding Applications
This relay controller was developed for users with low-current, low-signal switching applications such as telecommunications, networking, video, line-level audio, and much more.
This relay is equipped with terminal blocks for convenient connection of electronic devices.
This device uses DPDT relays. A single DPDT relay is made up of 2 SPDT switches. So each relay acts as two switches that are activated at the same time. This allows two independent signals to be switched at one time. In effect, there are two independent switches on a single DPDT relay. For an overview on all the types of relays offered on this site visit our Introduction to Computer Control Page.
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.
Even a no-frills design deserves a high-quality driver stage, and that's exactly what we put on this Relay controller. Fast-reacting flyback diodes help shunt dangerous voltages away from the driver circuit.
To control this Relay Controller, simply connect a data and ground wire between the board and computer or microcontroller. Provide +12 Volts DC to the board, and send ASCII character codes to control the relays.
This Relay Controller is 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.
Connect this board to the USB port of your computer using a USB to Serial adapter. The USB to Serial Adapter is to be used with the Quick Start Kit and is available at checkout.
![]() The above sample demonstrates control and status read of up to 8 Relays. Compatible with all Pro (NOT ProXR) Series Relay Controllers, Including 4 and 8-Channel SPDT and DPDT Versions. |
| The above screen shot shows one of the four available fully functioning Pro Series samples that are available with the NCD Component Library. View all the examples on our NCD Component Library Page. |
N-Button creates widgets or buttons to control up to eight relays without any programming. A new button will be created and placed on the desktop of your computer for each relay that you want to control. N-Button Lite supports Serial Port/ USB and Network connection between PC and relay board. N-Button Manager makes it easy to add any type of button to the desktop and change the properties.
| Relay Button widgets turn relays on/off directly. It has never been so easy to control relays before. | |||
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| Relay Status widgets show status of the relay automatically right on the desktop! | |||
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N-Button Lite is available as a free download. Look for the Desktop Control section to the right to download.
N-Button Lite version supports up to 8 widgets. If you want to add more than 8 widgets, you need upgrade to the standard version.
Also available is our QS12 Quick Start Kit. Kit includes a high quality regulated switcher supply, serial cables, and an RSIO adapter board used to add a standard serial and power connector to this relay controller. This Quick Start Kit can be purchased during checkout of this controller.
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NEW TO RS232 COMMUNICATIONS? GET STARTED HERE Click the above link for an exclusive article on RS232 Communications |
| RS232 Relay Article | RS232 Relay Article |
| Download Manual | Download the R45/R410 R85/R810 Pro Product Manual |
| E3C Complient | Download E3C Complient Specs |
| NCD Component Library | The NCD Component Library is a Plug-In for Visual Studio 2005/2008 that greatly reduces software development time, effectively reducing most control operations to a single line of code. This free download includes four example applications compatible with the Pro Series. |
| Wiring Diagrams | These wiring diagrams will help you understand how to connect to your devices and use relays as a form of control logic |
8-Channel 1-Amp DPDT RS-232 Relay Controller with Relay Interface | |
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Code: R81DPDTCN Price: $139.00 Shipping Weight: 1.00 pounds | |
| 8-Channel 1-Amp DPDT RS-232 Relay Controller with Relay Interface | |
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National Control Devices, LLCWorld's Largest Manufacturer of Computer Controlled Switching Devices Since 1995. |
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