XR83DPDTOC8LP XR Expansion Board
8-Channel 3A DPDT Relay + 8-Channel 150ma O.C. Output Expansion Relay Controller
- Onboard Open Collector Status LEDs
- Screw Terminal Connectors
- Power LEDs
- 2.1mm Power Connector
- Optional Power Supply
- Includes 6" XR Expansion Cable
- OC Outputs Allow Control of External Relays and Contactors
XR Expansion Relay Banks
XR Relay Expansion Controllers add a large variety of relay switching capabilities to an existing NCD device!
XR Expansion Ports are used to add banks of external relays to an NCD device. As we continue to develop new devices, a modular architecture will be implemented, offering the greatest amount of user flexibility. Separating the brawn from the brains allows us to continue to develop more intelligent controllers without making existing hardware obsolete.
Our Line of XR Expansion Relay Controllers add unlimited computer controlled switching potential, using a simple, modular upgrade path. From low power signal switching to high current, high voltage control, we offer an XR Expansion controller that will meet your switching requirements. Available with Single Pole Double Throw (SPDT) and Double Pole Double Throw (DPDT) relays, Open Collector Outputs (OC), and 8, 16, 24, or 32 outputs per expansion board.
Controlling XR Expansion Banks
XR Expansion Boards have no on-board brains. They are entirely reliant on the brains of a "master" device. A master device is an NCD controller with an XR expansion port and a microprocessor of some kind. Some master devices are wireless, and some master devices have digital I/O and analog to digital conversion capabilities. Some master devices also have on-board relays. When you run out of relays, just plug in an XR expansion controller that is equipped with the kind of relays you need.
The product manual for various NCD master devices will refer to a group of 8 relays as a relay bank. XR Expansion Modules count as 1, 2, 3, or 4 banks, depending on how many relays are on board (8, 16, 24, or 32).
As you continue to chain XR relay expansion controllers onto an XR expansion port, the total number of available relay banks will increase. Each master device is only capable of controlling a fixed number of relay banks. You should review the product manual of the master device you are using to determine the maximum number of supported relays banks. This modular expansion approach will allow you to chain relays of all kinds to a single NCD device.
Linking XR Expansion Boards Together
XR Expansion Boards include a 6" ribbon cable with a keyed connector, used to link the expansion controller to an NCD device. At the other end of the relay expansion board is an XR Pass-Through connector, allowing you to chain additional relay banks.
About Open Collectors
Open Collector Outputs are used primarily for the purposes of controlling external DC relays and some very small DC solenoids. An open collector output is different than a relay output. Open collector outputs allow the user to control the connection of an external device by connecting and disconnecting the ground wire under software control. To drive an external 12V relay, +12V should be connected to one side of the relay at all times. The other side of your relay should be connected to our Open Collector output. Use our open collector outputs to make the connection to ground under software control. Open Collector outputs are also known as low side drivers (meaning it switches the ground line). In this way, different devices of different voltages may be controlled, providing all power supplies can share a common ground. A relay can provide you with a simulated open collector output by simply by connecting one of the relay outputs to your power supply ground. For wiring diagrams, please see the XR manual page 8.