Description
USB Relay Devices from NCD
Our USB Relay products make it easy for computers of all types to control relays and monitor analog inputs. USB Relay boards allow you turn relays on or off, flash relays continuously, control relays for a duration of time, and control relays in groups using a cross-platform compatible USB interface. NCD ProXR Lite series controllers are a widely adopted standard used by industry for many years. Equipped with your choice of 1, 2, 4, or 8 on-board relays, the ProXR Lite series USB Relays suit the needs of most of our customers. Integrated Analog to Digital Converters may be used to manually control the relays, or they may be used to read external sensors. Equipped with 8 or 10-Bit resolution, the ADC built into NCD USB Relays add tremendous flexibility for various application requirements. This device includes a NCD USB Interface module which will mount as a Virtual COM port on your computer. Simply Open the COM port at 115.2K Baud and start communicating. The USB interface is compatible with all Windows, Linux, Mac, and Android operating systems. Most systems do not require a driver; however, we use FTDI interface chips in our products and drivers are available from their web site if required for your system (www.ftdichip.com).
Getting Started with an NCD USB Relay Module
Start by downloading Base Station at https://ncd.io/start. Plug in one of our USB relay boards and run Base Station. This software tool is designed to teach you all the features built into your controller and provide you with example commands. NCD USB Relays mount as a virtual COM port on your PC. Simply choose the new COM port and click OK to begin communicating with the USB Relay board. Base Station was written for Windows using Visual Studio (source code available). Base Station shows you all the commands you need for controlling relays and monitoring external sensors.
New Version Now Shipping
Beginning Late 2020, we’ve made some updates to this product to make it better with increased component count while maintaining the same functionality and footprint. The New Rev G2 Series adds a better power supply circuit to improve noise immunity while providing increased power to the communications socket. We also improved the relay drive circuit to better handle inductive loads. We also changed the color of the circuit board to Black and updated the branding to ncd.io with updated logos.
This is the same product you have been buying for years, but now with improved electronics and while maintaining the same footprint as the original design. Most importantly, this is now a Legacy product, which means it will never go obsolete as long as critical parts are still available to us. Built with our new high-speed pick and place assembly line, we can complete the surface mount assembly process at a rate of several thousand units per day with the potential to scale to any volume you could imagine, so you never need to worry about supply quantities or supply chain problems.
Please note that it was necessary for us to remove the integrated temperature sensor in select versions of this product. This sensor was providing incorrect readings if the relays were active for extended periods of time. We can help you with an off-board sensor if needed.
Updated Features
- Updated Logos and Branding, Changed PCB Color to Black
- Improved Relay Drive Circuit for Greater Noise Immunity
- Improved Power Supply Circuit using a Switcher Regulator for Lower Heat and Higher Power
- Adds Compatibility with NCDD5500 Ethernet and our WiFi/Bluetooth Communication Modules
- Use MQTT to Talk to this Device from the Internet when using our New WiFi Module
- Use Integrated Web Page to Control This Device when using our New Ethernet or WiFi Module
- Added Zip Tie Holes Near the Communications Module for a More Secure Installation
- New Option for Pluggable Connectors on the Analog Inputs
- Ferrite Beads Added to Better Separate Logic and Drive Circuits from Noise
- Migrated to Commonly Available LEDs to Address Supply Chain Limitations
- 100% Identical Firmware with No Changes for Drop In Replacement Compatibility
- 99% Identical Shape – Only Slight Changes to Connector Positioning for Better Fit and Finish
- Now Built by our High-Speed Pick and Place Machine for High-Volume Applications
- Legacy Status Product – Will Not Become Obsolete
- Removed Faulty Temperature Sensor from Select Versions due to Errant Readings
Base Station Software
Base Station Software was designed to help you learn the ProXR command set. Explore ProXR features using our Graphical User Interface. Watch data bytes flow to and from the board, so you easily understand the command execution process. There is no faster or easier way to learn how to automate than Base Station, as it was designed to work with our complete array of communication modules, including Wireless, Ethernet, USB, RS-232, and many more. You only need a Windows 8 or 10 Computer to Run Base Station. Base Station was written in Visual Studio, and we even provide the source code to help you on your way! Learn More about Base Station Software Here.

AD8 8-Channel 8/10-Bit Analog to Digital Converters

This controller is equipped with 8-Channels of 8/10-Bit Analog to Digital Converters, capable of reading analog voltages from 0 to 5 Volts DC. The ADCs on this controller allow monitoring of external sensors or contact closure input detection. Connect external temperature sensors, light sensors, current sensors, buttons, switches, or anything else that generates a 0-5VDC analog or contact closure output. With 8-bit resolution, analog inputs will convert 0-5 Volt signals into a value from 0 to 255. With 10-bit resolution, values of 0 to 1023 may be measured. Input resolution is software selected. Simply ask the controller for the analog value of each input, and the controller instantly responds.
Relay Activator and Analog Inputs
The Relay Activator control panel allows analog inputs to directly control relays. Simply connect the analog inputs to buttons or switches and trigger basic relay on or off functions to take manual control of the on-board relays. The Relay Activator control panel allows you to define 8 functions for each of the 8 inputs. Functions include turning relays on or off, toggling the state of relays, momentarily flash a relay, momentarily toggle the flashing function of a relay, turn all relays on, turn all relays off, and push notification events. When push notification events are configured, the controller generates a packet of data every time the inputs change state.

Learn More about ProXR Series Controllers
Base Station helps you learn how to use ProXR Series relay controllers. In this video, we will cover some of the most commonly used features.
Download Base Station
Download the Latest Version of Base Station and Source Code for Visual Studio.
ProXR Quick Start Guide
Online Manual for ProXR and ProXR Lite Series Controllers
Good to Know!
NCD ProXR Series Controllers have been in production for many years and have amassed a large user base since their initial release in the early 2000s. Due to the large client base, we have no plans to discontinue this line of products. In many cases, we are upgrading these devices to make them compatible with automated assembly processes along with improved driver and power electronics capable of supporting many communication technology changes well into the future. Rest assured, ProXR will continue to be a stable part of our product line for many years to come. ProXR series controllers manufactured with a Black circuit board have been migrated to automated assembly and are considered to be the final iteration of this product. These devices can be manufactured in high volumes in a much shorter period of time.
LabVIEW Relay Control

NCD supports integration of NCD relay controllers using LabVIEW. We have included samples and drivers for basic and advanced operation which cover most functions including Relay Timers. We have posted several tutorials on this topic here.
ProXR Lite Communication Options
We take communications seriously, as we believe in modular communications and firmware that properly supports scalability into future interface technologies. ProXR controllers support API communications, which effectively wrap every command with a header, payload, and checksum to ensure reliability. NCD API commands increase processing speed because no serial timeout is required prior to command processing. NCD API commands increase reliability, as only a proper checksum will authenticate a command and allow it to process. When we first implemented API, internet communications via a TCP/IP socket could be realized because the timing problems of internet communications were eliminated. While API is optional, it is strongly advised. Our Base Station software uses API communications, so it’s possible to control a ProXR controller over the internet after configuring port forwarding on your router.
ProXR series controllers are the world’s most adaptable controllers, capable of communicating with a wide variety of communication options. Pick any of your favorite communication technologies: Bluetooth, USB, WiFi, Ethernet, Key Fob, RS-485 or RS-232. ProXR easily adapts to the communication technologies you need most. We are committed to modular communications, so your ProXR series controllers can easily be retrofitted for other applications as your needs change. ProXR controllers are never obsolete, as we are actively releasing new communication technologies that greatly enhance the connectivity of our ProXR series controllers.
Communications Module Included

USB Communications Module
Our USB interface module makes it easy to control our devices using the USB port. Simply plug into any available USB port and start controlling our devices using standard serial commands. NCD USB Interface modules feature genuine FTDI USB to Serial Converter Chips, the very best in the industry. Learn more about our USB Communications module here.
Relay Options

10-Amp SPDT Signal Relay Option
This controller is available with a 10-Amp relay option, allowing control of higher-power loads up to an absolute maximum of 240VAC at 10 Amps. Ideal for general purpose switching applications, this relays is focused on power-switching, and should never be used for low-power signals due to a higher On resistance of up to 150 Ohms when relay contacts are new (contact resistance drops to less than 1 Ohm after break-in period). The 10-Amp relay is of the SPDT variety, which provides Common (C), Normally Open (NO), and Normally Closed (NC) connections. Common is connected to NC when the relay is off. Common disconnects from NC and connects to NO when the relay is activated. All connections are made via screw terminals, capable of accepting up to 12 AWG wire. Review Datasheet

5-Amp SPDT Signal Relay Option
This controller is available with a 5-Amp relay option, allowing control of higher-power loads up to an absolute maximum of 240VAC at 5 Amps. Ideal for general purpose switching applications, this relays is focused on power-switching, and should never be used for low-power signals due to a higher On resistance of up to 150 Ohms when relay contacts are new (contact resistance drops to less than 1 Ohm after break-in period). The 5-Amp relay is of the SPDT variety, which provides Common (C), Normally Open (NO), and Normally Closed (NC) connections. Common is connected to NC when the relay is off. Common disconnects from NC and connects to NO when the relay is activated. All connections are made via screw terminals, capable of accepting up to 12 AWG wire. Review Datasheet