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T-Relay get it now

Overview

LILYGO T-Relay is an ESP32-based development board with integrated relay outputs. Powered by the ESP32-WROVER-E module (dual-core Xtensa LX6, 240 MHz), it combines Wi-Fi 4 (802.11 b/g/n) and Bluetooth 4.2 with 4 optocoupler-isolated relay channels capable of switching up to 250 V AC / 10 A or 28 V DC / 10 A. The board accepts a wide 5–24 V DC power input, exposes spare GPIOs on a header, and is compatible with Tasmota, ESPHome, and other ESP32 firmware frameworks. Ideal for smart home automation, remote switching, and industrial control applications.

Quick Start

Example Support

ExamplePlatformIO/ArduinoESP-IDFDescription
LilyGo-T-RelayRelay control, ESPHome, Tasmota examples

PlatformIO

  1. Install Visual Studio Code and Python
  2. Search for and install the PlatformIO IDE extension in VS Code
  3. Open the LilyGo-T-Relay project folder
  4. Open platformio.ini and select your example
  5. Click to compile, connect via USB-C, click to upload

Note: The board cannot be flashed via USB without the LilyGO T-U2T USB-to-serial adapter. Use the T-U2T or another CP210x/CH340 adapter connected to the UART header.

Arduino

  1. Install Arduino IDE
  2. Install Arduino ESP32
  3. In ToolsBoard, select ESP32 Wrover Module
  4. Set Partition Scheme to Huge APP (3MB No OTA/1MB SPIFFS)
  5. Set PSRAM to Enabled
  6. Click Upload

Key Features

  • ESP32-WROVER-E dual-core Xtensa LX6 @ 240 MHz, Wi-Fi + Bluetooth 4.2
  • 4 optocoupler-isolated relay channels (HRS4H-S-DC5V)
  • Relay contacts: 250 V AC / 10 A or 28 V DC / 10 A
  • Wide input voltage: 5–24 V DC
  • 4 MB Flash, 8 MB PSRAM
  • Blue LED status indicator per relay channel
  • All spare GPIOs broken out on a pin header
  • Compatible with Tasmota, ESPHome, ESPEasy

Specifications

ParameterValue
SOCESP32-WROVER-E (Xtensa dual-core LX6, 240 MHz)
Flash4 MB
PSRAM8 MB
WirelessWi-Fi 802.11 b/g/n, Bluetooth 4.2
Relay Channels4
Relay Rating250 V AC / 10 A, 28 V DC / 10 A
Input Voltage5–24 V DC
Logic Voltage3.3 V
USBUSB-C (power only; serial via T-U2T adapter)
Dimensions
Weight

T-Relay Specifications

Pin Diagram

T-Relay Pinout

RelayGPIO
K1GPIO21
K2GPIO19
K3GPIO18
K4GPIO5

Dimensions

Schematic

Datasheet

Software Libraries

Tasmota

FAQ

Changelog

VersionDateNotes
V1.0Initial release