Using the 3-Wire Expander with VEX V5

The 3-Wire Expander is a device which can be plugged into a V5 Brain’s Smart Port and creates eight additional locations to plug in 3-Wire devices.

Angled view of the V5 3-Wire Expander.


What is the 3-Wire Expander

V5 3-Wire Expander viewed from the side to show its Smart Port.

The 3-Wire Expander is a device used to add additional 3-Wire ports to the V5 Brain. The 3-Wire Expander has a V5 Smart Port on one end to connect to the V5 Brain and eight 3-Wire ports on the other.

V5 3-Wire Expander viewed from the other side to show its eight 3-Wire ports.

The other side of the 3-Wire Expander has eight 3-Wire ports.


Why use a 3-Wire Expander?

When beginning a project, it might seem impossible to use all eight 3-Wire Ports on the V5 Brain. However, as projects and robots become more advanced, the 3-Wire Ports quickly start to fill up.

Each device listed here requires the use of at least one 3-Wire Port.

V5 3-Wire Expander viewed from the side to show its eight 3-Wire ports.

The 3-Wire Ports on the V5 Brain can become quickly filled. The 3-Wire Expander can add eight additional ports and double the amount of 3-Wire Ports that can be used for advanced robotic behavior.


How to Use a 3-Wire Expander

V5 3-Wire Expander is shown connected to a V5 Brain using a Smart Cable.

The 3-Wire Expander can be plugged into any one of the 21 Smart Ports on the V5 Brain by connecting a V5 Smart Cable between the V5 Brain and the Smart Port on the expander.

Close up of a Smart Cable connected to the Smart Port of the 3-Wire Expander to indicate that the connection must be secure.

Be sure the Smart Cable is fully inserted and locked into the ports of both the V5 Brain and the 3-Wire Expander.

3-Wire cable is shown being connected to a 3-Wire port on the 3-Wire Expander. The 3-Wire cable is highlighted to indicate that its orientation matters.

Any 3-Wire device or a 3-Wire extension cable for a device can be plugged into any of the eight 3-Wire Ports on the 3-Wire Expander. Be sure the 3-Wire cable is fully inserted into the 3-Wire Port. The port and the 3-Wire cable both have a key which should only allow the cable to be plugged in with one orientation.

V5 3-Wire Expander viewed from the side to show its eight 3-Wire ports. The ports are labeled alphabetically from A to H.

The 3-Wire Ports on the 3-Wire Expander are designated sequential as ports A through H from left to right.

Application icon for VEXcode V5.

The 3-Wire Expander needs to be paired with VEXcode V5 or VEXcode Pro V5 to create a user project for the V5 Brain.


How to Mount a 3-Wire Expander

Bottom of the V5 Inertial Sensor with its one threaded insert for a #8-32 VEX screw and its round boss both labeled and highlighted.

The device can be easily mounted to any piece of the VEX structural metal.

The 3-Wire Expander has a mounting hole. This mounting hole passes through the device in which a screw can be placed. This screw can then be inserted into the hole of a piece of structural metal to be attached with a nut. On the bottom of the 3-Wire Expander is a round boss which will fit into a hole of the structural metal and provide a second point of contact for the device.


How to configure devices with the 3-Wire Expander

Application icon for VEXcode V5.

Launch VEXcode V5

VEXcode V5 Toolbar with the Devices icon highlighted in between the Code Viewer and Print Console icons.

Select the Devices icon.

VEXcode V5 Devices menu with the Add a device button highlighted.

Select ‘Add a device.’

VEXcode V5 Devices menu after the Add a device button has been selected. The 3-Wire Expander option is highlighted.

Select ‘3-WIRE EXPANDER.’

VEXcode V5 Devices menu after setting the new 3-Wire Expander's Smart Port option to 1. Below, the Done button is highlighted.

Select the Smart Port that the 3-Wire Expander is plugged into on the V5 Brain. Once the port is chosen, select ‘DONE.’

Note: the name of the 3-Wire Expander can be changed in the text window from Expander1 to a different name. For more information on how to change the name of devices, view the 3-Wire Devices article from the VEX Library.

VEXcode V5 Devices menu with the Add a device button highlighted.

To add a 3-Wire device to the Expander, select ‘Add a device’.

Note: in this example, assume there is a Bumper Switch plugged into 3-Wire Port “A” on the 3-Wire Expander.

VEXcode V5 Devices menu after the Add a device button has been selected. The 3-Wire option is highlighted.

Select ‘3-WIRE.’

VEXcode V5 Devices menu after the 3-Wire device option has been selected. There is a menu of 3-Wire Devices shown, and the Bumper option is highlighted.

Select ‘BUMPER.’

VEXcode V5 Devices menu with the ports options for the new 3-Wire device shown. Above, there are options to choose between the Brain's 3-Wire ports or an Expander's 3-Wire ports, in this example the Expander's name is shown as Expander1. In this example, the A port on the Expander1 has been selected. Below, the Done button is highlighted.

Under ‘Select 3-Wire Source,’ select ‘Expander1.’ The port also needs to be selected. Select port ‘A,’ then ‘DONE’ to finish the Device Setup.

For more on 3-wire Port Architecture

For more information, help, and tips, check out the many resources at VEX Professional Development Plus

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