USB Relay Controller, 3 Contacts, Form C, 10A, 250V AC/24V DC, Bus-Powered

SKU:: 359
Manufacturer:: Tokyo Devices
Model Number:: TDFA30303
EAN:: 4560457401400
Released on:: Feb 2026
Category:: Relay and Digital I/O

TDFA30301 is a simple USB-controlled relay board. It allows you to switch 12/24VDC, or 100/250VAC loads via USB. It can be controlled from both Windows and Linux.

Operates via USB connection (bus-powered). Can also be used from board PCs such as Raspberry Pi and Armadillo.
The contact rating supports up to 10A at 250VAC or 10A at 24VDC. Ideal for controlling mains power or 12/24V systems via USB.
Multiple devices can be controlled from a single PC. It is also possible to connect dozens of units using a USB hub.
Simple control commands are provided for Windows/Linux. Easy to integrate into applications.
Suitable for applications across industrial, research, security, and other fields.
Can be mounted on a DIN rail by using the optional DIN mount kit (part number: TDAC-DMK).
Uses highly reliable components from industrial manufacturers for the relay, terminal block, and all other parts.

How to Use

The terminal block has three terminals: NO, COM, and NC. When the relay is ON, COM–NO is connected and COM–NC is disconnected. When the relay is OFF, COM–NO is disconnected and COM–NC is connected.

USB control uses Tokyo Devices’ standard control command set, “TD-USB”.

``` (Turn relays ON: 011b = 3)

td-usb tdfa30303 set 3

(Turn all relays OFF)

td-usb tdfa30303 set 0 ```

To use it from your own application, call TD-USB as an external command. It can be used from Python, shell scripts, C#, LabVIEW, etc. For details, see the samples in the TD-USB documentation.

Package Contents

PCB module unit

Note: A USB cable (USB Type-A to Mini-B) is required separately. (Part number: TDAC-USB2B1M5)

Specifications

Item	Value
Relay rating	250V AC 10A, 24V DC 10A
Relay contacts	3c (SPDT-CO)
Terminal specification	Screw clamp, 0.75–2.5 mm², 26–14 AWG
Interface	USB 2.0 Full Speed
Current consumption	200 mA max.
Dimensions	80 × 61 × 20 mm
Power supply	USB bus power
Supported OS	Windows 7 or later (64-bit) / Linux