8 Relays Expander. Hardware Guide.
This guide will help you connect and configure the relay expander to the ESP32R4 controller.
The relay expander increases the number of relays controlled by the ESP32R4 controller. Can connect up to 12 expanders with 8 relays each.
Hardware:
Power supply select:
- DC IN voltage 7~36V. External DC power supply. Minimal power 1A.
- I2C line power IN. 5V Power IN from ESP32R4 controller. Need to control the total power loads for the controller and I2C expanders. If ESP32R4 controller has power from AC-DC (~0.7A), it is enough for 1-2 expansion boards. If ESP32R4 controller has DC power IN, needs a minimal supply of 1.7A (0.7A for ESP32R4 + 0.8A for relays expander), it needs to power more expander, use a power supply for ~3A.
I2C address selection： For each I2C device, you need to select a UNIQUE address. Use the jumpers to set the address. Address 0x20 – 0x27 (or 0x38 – 0x3F). Use jumpers for selecting addresses. The description of the address you can find on the board. Some firmware have reserved addresses. Pls, follow of firmware instructions.
Connection to the controller: The expansion board has included I2C connection cable. This cable needs to connect to I2C pin header (GND, 5V, SDA, SCL) of ESP32R4 controller board.
Firmware:
For firmware settings follow these instructions: