8-Channel Programmable Potentiometer with USB Interface

Digital Potentiomer

You've been asking for NCD to bring back their Digital Potentiometer and they heard you!  Back in production as a Legacy controller, this device will not become obsolete as long as Parts Remain Available!  Based on the MCP42xx0 Series Digital Potentiometers, use a computer to change the resistor values on 8 different programmable resistors with up to 256 taps per potentiometer.  Available in Potentiometer values of 10 kΩ, 50 kΩ and 100 kΩ with a wiper current of up to 1mA per channel.  Set the Power-Up Default State of the first 32 Potentiometers or read the Power-Up Default State of Each Potentiometer.  All other Potentiometers default to a center position for all wipers.

Resistance Output

Potentiometers have 3 Connections: A, Wiper, and B. When a low value is sent to the controller, the wiper moves closer to A, decreasing the resistance between A and the wiper (increasing the resistance between the wiper and B).  When a high value is sent to the controller, the wiper moves closer to B, decreasing the resistance between the wiper and B (increasing the resistance between the wiper and A).  The first 32 channels of wiper values can be set to a power-up default state.  It is possible to set the wipers on all outputs individually or simultaneously.

Send Commands to Program the Output Resistance

You can send commands to program the output resistance of each individual output, or you program all outputs at the same time.  Other commands allow you to set the startup resistance of each output.  The ProXR command set allows you to send commands to activate relays, deactivate relays, control all the relays at one time, plus you can send commands that tell a relay to turn on for a few seconds, minutes, or hours.  You can assign 16 timers to any of the 256 relays, and set the timers to go off after the duration has expired.

Expandable as Your Needs Grow

Built on the ProXR Framework, the ProXR Series has a long history of reliability while maintaining an easy learning curve using our Base Station Software as a guide for controlling and using this product.  Equipped with a UXP expansion port, add up to 256 Potentiometer Channels by chaining expansions to this main controller board.  Equipped with a XR Expansion port, this device is capable of controlling up to 256 relays of various types using XR Series relay controllers.  Simply plug in any XR Expansion Relay Controller and you are ready to switch solid state relays, DPDT signal relays, general purpose SPDT relays, and high-power relays.  Supports simple relay control commands such as off, on, or toggle functions as well as more complex commands for activating relays using integrated timers.

New Version Shipping

Beginning Late 2020, NCD 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 availability.  We als changed the color of the circuit board to Black and updated branding to ncd.io with updated logos.

Legacy Product

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 their new high-speed pick and place assembly line, they 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.

More Interfaces Available

This controller features a modular communications interface, capable of accepting USB, RS-232, Ethernet, WiFi, Bluetooth, communication modules.  Control potentiometers directly from cloud platforms such as Amazon AWS or MQTT when working with our WiFi Bluetooth USB Communications module.  Control Potentiometers using a USB Interface and a Virtual COM Port communications when using our USB interface.  Control Potentiometers over WiFi or Ethernet by opening a TCP socket to port 2101 and start sending commands (as shown in Base Station).

Base Station Compatible

Use Base Station software to quickly learn the command structure for potentiometer control using a simple Point and Click interface that supports all communication technologies.

Resistance Output

Please keep in mind; our POT series controllers offer a resistance output, and cannot provide a voltage output of any kind without additional electronics.  The potentiometers are limited to applications that operate in the 0 to 5V range.  Each potentiometer has a maximum current capacity of 1ma.  Exceeding these rating will immediately damage the controller.

Connections

Potentiometers have 3 Connections: A, Wiper, and B. When a low value is sent to the controller, the wiper moves closer to A, decreasing the resistance between A and the wiper (increasing the resistance between the wiper and B).  When a high value is sent to the controller, the wiper moves closer to B, decreasing the resistance between the wiper and B (increasing the resistance between the wiper and A). The first 48 channels of wiper values can be set to a power-up default state.  It is possible to set the wipers on all outputs individually or simultaneously. 

Output Resistance

Send commands to program the output resistance of each individual output, or you program all outputs at the same time.  Other commands allow you to set the startup resistance of each output.  The ProXR command set allows you to send commands to activate relays, deactivate relays, control all the relays at one time, plus you can send commands that tell a relay to turn on for a few seconds, minutes, or hours.  You can assign 16 timers to any of the 256 relays, and set the timers to go off after the duration has expired.  The complete command set can be found in the ProXR Quick Start Guide located in the Data Sheets tab above.

This Board is RoHS Compliant

This board is led free and RoHS Compliant.  If your requirements are for RoHS compliant parts this board is manufactured with RoHS compliant led free parts and solder.

Precautions

This is an expansion module and must be connected to a compatible board to work.  This board will NOT work on it's own.  Please keep in mind; our POT series controllers offer a resistance output, and cannot provide a voltage output of any kind without additional electronics.  Integrated potentiometers are limited to applications that operate in the 0 to 5V range.  Each potentiometer has a maximum current capacity of 1ma.  Exceeding these rating will immediately damage the board.

USB Relay Control

Mounts as a Virtual COM Port

The USB Relay connects directly to your computer's USB port and appears as a standard COM port. On Windows machines with internet access, the correct FTDI drivers install automatically.

Once powered, the board listens for compact serial commands - typically 2 - 6 bytes. After processing your command, it returns ASCII code 85 to confirm successful completion.

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USB Communications Module

The USB Relay module makes controlling relays simple. Plug it into any available USB port and begin sending standard serial commands to switch relays or read A/D inputs.

Every NCD USB interface uses a genuine FTDI FT232-RL USB-to-Serial converter chip for maximum stability and cross-platform support. With drivers available for Windows, macOS, Linux, and more, the module communicates using a Virtual COM Port for easy software integration.

Once installed, open the COM port at 115.2K baud and start exchanging data immediately. On-board USB, TX, and RX LEDs provide live communication feedback. The module uses a durable USB Mini connector - our preferred interface for longevity and reliability.

Simply download the latest Base Station Software, install it on your Windows PC, and your COM port will appear automatically, ready for communication.

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Virtual COM Port

A Virtual COM Port (VCP) registers as a standard serial port on your computer, allowing you to use new or existing serial-based software with any NCD Industrial controller.

Because VCP communication is one of the easiest and most universally supported communication formats across operating systems, languages, and hardware platforms, the ZUSB USB Interface is the ideal tool for learning, testing, and operating NCD devices.

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Induction Considerations

For most applications, the onboard capacitors provide more than enough suppression, and users will never encounter communication issues.

However, switching inductive loads such as motors can create higher levels of electrical noise, and in those situations additional precautions may be necessary. Testing is recommended for motor-based installations to ensure reliable communication.

If communication problems do occur in these high-induction environments:

• An RS-232 communications module provides a more noise-resistant interface.
• When USB connectivity is still needed, a USB-to-RS-232 adapter paired with the RS-232 module offers the stability of RS-232 with the convenience of USB.
• RS-232 naturally blocks induction to safer levels, allowing the adapter to operate without errors even in demanding motor-control setups.

For all other users and non-motor applications, standard USB operation typically performs without complications.

The XR Expansion Port

Add Relays as Your Needs Grow

ProXR Controllers were built with relay expansion in mind. The XR Expansion Port lets you add banks of external relays to any ProXR or Taralist board equipped with an XR Expansion port. Expansion boards can be added at any time as your system grows, up to a maximum of 256 total relays.

As expansion boards are added, additional relay banks become available automatically. Simply add another expansion board whenever you need more relays.

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Relay Banks - How Large Systems Stay Simple

ProXR and ProXR Lite controllers organize relays into groups of eight called banks.

Each bank contains:

• Relay 1 through Relay 8

Expandable ProXR boards can add additional banks using XR expansion boards as your system grows.

For example:

• An 8-relay controller uses one bank
• A 32-relay controller uses four banks
• A 64-relay setup uses eight banks

Instead of creating a different command for every relay in a large system, the ProXR firmware lets you:

• Select a bank
• Send simple relay commands within that bank

This keeps the command structure fast, compact, and easy to manage - from a single-bank ProXR Lite installation to large, multi-bank ProXR expansion systems. From a single 8-relay board to a fully expanded 256-relay system, the command structure does not change.

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Linking XR Expansion Boards Together

XR Expansion Boards include both an XR Input and XR Output connector. Connect the XR Output on your ProXR controller to the XR Input on the first expansion board. To add more relays, connect the XR Output of one expansion board to the XR Input of the next board in the chain.

You can mix and match different relay types on expansion boards to match your application. A 6" expansion cable is included with each expansion board.

For best reliability, keep all expansion cabling as short as possible. Maximum expansion length and total relay count depend on your installation, electrical noise, and overall cable length. For best compatibility, the combined length of the controller, expansion boards, and cables should not exceed 1-2 meters.

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Will Not Operate Independently

This Expansion Board gets it's commands from the main ProXR or Taralist board and will not operate independently.  This board MUST be plugged into a ProXR or Taralist board to operate and will not function on it's own.

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Mix & Match

Expansion boards do not need to match the relay type or amperage of the main controller or other expansion boards. Mix and match expansion boards to get the exact relay types and current ratings your application requires.

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Essential Power Requirements

All XR expansion boards require their own 12 VDC power source. A regulated 12 VDC supply must be connected directly to each expansion board for proper operation.

We offer a compatible wall-plug power supply at checkout, or you may use your own regulated 12 VDC supply. Learn More

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Maximum Relay Rating Notes

ProXR is capable of expanding to an absolute maximum of 256 Relays.  In some cases, it may not be possible to control all 256 relays, particularly in applications where high noise levels may be involved.  Experimentation may be required, as it is not possible for us to guarantee all users will be able to utilize all 256 relays in every application.  Noise tends to accumulate when several expansions are connected together.  For best results, the XR expansion cables must be as short as possible.

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This Board is RoHS Compliant

This board is led free and RoHS Compliant.  If your requirements are for RoHS compliant parts this board is manufactured with RoHS compliant led free parts and solder.

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2-Million Cycles

XR Expansion Boards are designed for long life just as the ProXR boards, you should expect to get years of service from expansion board and literally 2-million cycles from the relays on board.  With a 5-year warranty and a money back guarantee add more relay anytime the need arises!

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Accessories

Data Sheets & Quick Start Guides

Below are the Data Sheets Quick Start Guides for this board.  These are the guides that will help you communicate and configure this board.