The XR Expansion Port

Add Relays as Your Needs Grow

ProXR Controllers were built with relay expansion in mind.  The XR Expansion Port is used to add banks of external relays to a ProXR or Taralist board equipped with a XR Expansion port.  The ProXR and Taralist boards are fitted with an XR Expansion Port where you can add expansion boards.  Expansion boards can be added until you reach 256 total relays.  As you continue to chain expansion boards onto an XR expansion port, the total number of available relay banks will increase.  Add expansion boards as needed in the future, whenever you require more relays simply order another expansion board.

Linking XR Expansion Boards Together

XR Expansion Boards consist of a XR Input and XR Output Connector.  Simply connect the XR Output of your ProXR Board to the XR Input located on the relay expansion board.  Chaining more relays is easy.  Simply connect the XR Output of your ProXR expansion board to the XR Input of your next expansion board.  Mix and Match different relay types as your application requires.  A 6″ expansion cable is included with the expansion board.  It's important to keep the cabling as short as possible.  Not all users will be able to expand to 256 total relays, as it all depends on the installation, the amount of electrical interference, and the overall cable length.  For best compatibility, the total length of the ProXR controller and all of the expansions and cabling should not exceed 1 or 2 meters.

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.

Essential Power Requirements

This and all expansion boards require 12 VDC to operate.  We offer a wall-wart type power supply at checkout if you need to plug this into a 110 wall outlet.  Applying Good clean power to the board is essential for the operation of the board.  Without good steady clean power from a regulated power supply the board simply will not function correctly.  The PWR12 US power supply is a 120VAC to 12VDC 1.25A 60Hz regulated power supply and it plugs into the barrel connector on the board.  The output connector is a 2.1mm I.D. x 5.5mm O.D. x 9.5mm Female R/A barrel connector.  We also carry an international power supply with interchangeable adapters for international customers. Learn More

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.

DPDT Relays Installed

This board has DPDT relays installed.  A single DPDT relay is made up of 2 SPDT switches.  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 - they will always switch together.

There are two connectors with Normally Open, Normally Closed and Common for each relay allowing two separate connections.  The picture above shows the 4-channel connectors.  The diagram to the right shows the how the arms of the common connector swing from the Normally Closed to the Normally Open positions when energized.  Wiring to either the NO or NC can produce your desired results.

Mix & Match

Expansion boards do not need to be the same relay amperage as the main board or other expansion boards.  Mix & match expansion board to get the exact amperage for your switching needs. 

2-Million Cycles

ProXR series controllers are designed for long life, you should expect to get years of service from your controller and literally 2-million cycles from the relays on board.  With a 5-year warranty and a money back guarantee you have nothing to loose!  Place your order now, while everything is in front of you.

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.

5-Year Warranty/Money Back Guarantee

ProXR Lite series controllers are guaranteed against manufacturing and functionality defects for a full 5 years!  Not to mention a 30-day money back guarantee!  If for any reason you are not happy with a relay purchased from Relay Pros, simply return it within 30 days and we will give you your money back!  Controllers that are damaged by our customers will not of course be warranted under any circumstances. 

Shipping

The boards sold are brand new units shipped from our office conveniently located in Missouri.  These boards are completely tested before they are released for shipping  With so many boards on our site it is impossible to stock boards, please allow two to three days production time for your order to ship.  If you have any questions please feel free to call our office at 800-960-4287 or e-mail us at sales@relaypros.com.

Relay Logic

Relay Wiring Samples

This page provides simple examples showing how to wire a single relay - or multiple relays - for common switching applications. We use a light as the example load, but you can substitute a gate controller, security panel input, dry contact device, motor trigger, or most other switched loads. These wiring samples demonstrate different ways to connect relays to achieve the switching behavior you need.

Get a printout of this page

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SPDT Wiring

SPDT (Single Pole Double Throw) relays include three terminals: Common (COM), Normally Open (NO), and Normally Closed (NC).

• When the relay is off, COM is connected to NC.
• When the relay is energized, COM switches to NO.

Your load can be wired to either the NO or NC terminal depending on whether you want the device to turn on when the relay activates or when it releases. Examples below demonstrate both wiring methods.

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SPST Wiring

SPST (Single Pole Single Throw) relays provide two terminals: Common (COM) and Normally Open (NO).

When the relay coil is energized, COM connects to NO to power the load. The only SPST relays offered on this site are our 30-Amp models. All SPST examples shown on this page apply to these relays as long as the example does not require a Normally Closed terminal.

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DPDT Wiring

A DPDT (Double Pole Double Throw) relay contains two SPDT switches that operate together.

• Each side includes its own COM, NO, and NC terminals.
• Both internal switches change state at the same time.

This allows you to control two independent circuits with one relay. Wiring for each side of a DPDT relay follows the same rules as an SPDT relay, so the examples on this page apply directly.

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Relay Logic Examples

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Example 1 - Simple Off/On Control

This example shows the most basic way to use a relay to switch a device such as a light. When the relay energizes, its NO (Normally Open) contact closes to COM (Common), completing the circuit and turning the light on.

Only a single power wire is switched in this setup, making it the simplest method for controlling a light - or any device - using a relay.

Use this example for switching a light or any device you want to power only when the relay is on.

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Example 2 - Simple On/Off (Using NC Contact)

This wiring method keeps the device on by default. The relay switches a single power wire through the COM (Common) and NC (Normally Closed) terminals.
When the relay is not energized, the NC contact is closed to COM and the light remains on.
When the relay energizes, the NC contact opens, interrupting power and turning the light off.

This approach is ideal for devices that stay on most of the time, reducing relay wear since it doesn't need to remain energized to keep the device powered. It's also a useful method for power-cycling equipment - energizing the relay momentarily will turn the device off.

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Example 3 - AND Logic Using Two Relays

This example shows how two relays can work together so a light turns on only when both relays are energized. This creates an AND Logic condition:
Relay 1 AND Relay 2 must be on for the light to receive power.

A single power wire is switched, but it must pass through both relay contacts before reaching the light. This setup is ideal when two conditions must be met at the same time - such as requiring input from multiple sensors or system parameters.

MirC/MirX Users: This wiring requires two contact closure inputs on the sender board before the receiver's relay activates. Use this approach when two independent outputs must close before turning on the light.

For example, a light could turn on only when:
• A light sensor detects it's dark AND
• A motion sensor detects activity in the room

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Example 4 - AND Logic Using Three Relays

This example expands on the previous AND Logic concept. Here, the light will turn on only when all three relays are energized:

Relay 1 AND Relay 2 AND Relay 3 must be on for power to reach the light.

A single power wire is routed through all three relay contacts. Wiring from the NO (Normally Open) of Relay 1 to the COM (Common) of Relay 2, then from the NO of Relay 2 to the COM of Relay 3, creates a series path that requires every relay to close before the light can activate.

This method can be scaled easily - just continue wiring NO of each relay to the COM of the next relay. Add as many relays as needed to meet your logic or safety requirements.

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Example 5 - Override Function

This example demonstrates the and/or function. The light bulb will be activated if Relay 1 and Relay 2 are energized OR if Relay 3 is energized. This example is great for applications that may require a logical condition of 2 relays plus an override feature. For instance, if Relay 1 is a night/day sensor, Relay 2 is a moisture sensor. If its dark and the soil is dry, Relays 1 and 2 can activate a pump. If you want to override these conditions with local physical switch using Relay Activator function (see the AD8 Command Set Tab) Relay 3 would override Relays 1 & 2.

MirC/MirX Users: Add a manual button or switch to control the third relay to manually control the light if you have sensors that control the other relays.

Reactor Users: Add a manual button or switch to control the third relay to manually control the light if you have sensors that control the other relays.

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Example 6 - Either Relay Activates

This example demonstrates how either relay can be used to activate a light. Only one power wire is switched in this example using either of two relays to turn on the light. In this sample, only one activated relay is required to activate the light. If both relays are activated, the light will be on. Great for if you have a timer for one of the relays but want to turn the light on when the timer is scheduled off or have two sensors connected and want either of them to control a device.

MirC/MirX Users: Two contact closure inputs in the sender board and either of the inputs can control one light or device.

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Example 7 - 3-Way Switch

This example demonstrates how to create a 3-way light switch to activate a light. A 3-way light switch is where two light switches can be used to activate a single light. This sample is exactly the same as a 3-way light switch, the only difference being each physical switch is replaced by a relay. Operationally, it works the same way. Only one power wire is switched in this example using both relays to turn on the light. Each relay activation will cause the light to toggle. Switching two relays at one time is like flipping 2 switches at once....with the same result. This sample is particularly useful since you can replace one relay (as shown in the diagram) with a physical light switch. This will allow a computer to control a light as well as manual operation of a light. Properly used, this can be one of the most valuable diagrams we offer on this page.

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Example 8 - Motor Control

This example demonstrates how to control the direction of a DC motor using 2 relays. Braking is accomplished by connecting both motor terminals to a common power connection (Faraday's Law). The capacitors shown may not be required for small motors, but if you experience problems with relays shutting themselves off, the induction suppression capacitor will be required. The .1uF capacitor helps suppress electronic noise if the battery were to be used by sensitive devices (such as radios/amplifiers).

• Relay 1 Off Relay 2 Off = Motor Brake to +
• Relay 1 On Relay 2 Off = Motor Forward
• Relay 1 Off Relay 2 On = Motor Backward
• Relay 1 On Relay 2 On = Motor Brake to -
• Induction Capacitor Should Be located by relay
• Filter Capacitor Should be Located Near Motor
• Additional Capacitors May be Desirable for Some Motors

Inductive loads typically require 2-3 times the runtime voltage or amperage when power is first applied to the device. For instance, a motor rate at 5 Amps, 125 VAC will often require 10-15 amps just to get the shaft of the motor in motion. Once in motion, the the motor may consume no more than 5 amps. When driving these types of loads, choose a relay that exceeds the initial requirement of the motor. In this case, a 20-30 Amp relay should be used for best relay life.

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.

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