1. Prodotto finitoview
The DORHEA ESP32 WiFi 4 Channel Relay Module is a versatile development board designed for smart home and wireless control applications. It integrates the robust ESP32-WROOM-32E module, offering WiFi connectivity and a large 4MByte Flash memory. The module features four independent 5V relays, capable of switching various loads. It supports flexible power input options, including AC220V and DC5-30V, and is compatible with the Arduino IDE for easy programming and development.

Figura 1: Fronte e retro view of the ESP32 WiFi 4 Channel Relay Module.
2 Caratteristiche
- Integrated ESP32-WROOM-32E WiFi module with 4MByte Flash.
- Flexible power supply: Supports AC220V or DC5-30V input.
- Four 5V relays with output switch signals, suitable for controlling loads up to AC250V/DC30V.
- Includes an RST reset button and a programmable button for user interaction.
- I/O ports and UART program download port are exposed for secondary development.
- Features 1 programmable LED and individual relay indicator LEDs.

Figura 2: dettagliata views of key components on the module, including the ESP32 chip, relays, and power input section.
3. Contenuto della confezione
Il pacchetto include i seguenti articoli:
- 1 x AC/DC Power Supply ESP32 Four-Way Relay Module
- 2 x 10 Double Row Pin Headers
- 1 x 6 Single Row Pin Header
- 1 x Single Line Cap

Figure 3: The ESP32 relay module along with the included pin headers for connectivity.
4. Istruzioni per l'installazione
Follow these steps to set up your ESP32 WiFi 4 Channel Relay Module:
4.1. Component Identification and Pinout
Before connecting, familiarize yourself with the module's components and pin assignments. Refer to the diagram below for a clear understanding of each terminal and indicator.

Figure 4: Labeled diagram of the module's connections and features.
- AC 220V Power Supply: Connect your AC 220V power source here.
- DC 7-30V Power Supply: Connect your DC 7-30V power source here.
- TERRA: Ground connection for DC power.
- Alimentazione 5V: 5V output for external components.
- Spia luminosa del relè: LEDs that illuminate when the corresponding relay is active.
- Indicatore luminoso di alimentazione: Indicates the module is powered on.
- Programmable LED: A user-controllable LED.
- ESP-32E: The main ESP32-WROOM-32E module.
- Pulsante di reset: Reimposta il modulo ESP32.
- Relay Connections (NO, COM, NC): Each of the four relays has Normally Open (NO), Common (COM), and Normally Closed (NC) terminals for connecting loads.
4.2. Collegamento dell'alimentazione
Choose one of the following power supply methods:
- Alimentazione CA: Connect AC 220V to the designated AC 220V terminals (L and N).
- Potenza CC: Connect DC 7-30V to the DC 7-30V terminals, ensuring correct polarity (positive to VCC, negative to GND).
Caution: Ensure only one power source is connected at a time. Incorrect wiring can damage the module or connected devices.
4.3. Connecting Loads to Relays
Each relay provides three terminals: Normally Open (NO), Common (COM), and Normally Closed (NC). To control a load:
- For a load that should be SPENTO when the relay is inactive and ON when active, connect one side of the load to the COM terminal and the other side to the NO terminale.
- For a load that should be ON when the relay is inactive and SPENTO when active, connect one side of the load to the COM terminal and the other side to the NC terminale.
Warning: Always ensure the load's voltage and current ratings are within the relay's specifications (AC250V/DC30V, 10A) to prevent damage or hazards.
4.4. Programmazione del modulo
The module can be programmed using the Arduino IDE. You will need a USB to TTL adapter to connect the module's UART program download port to your computer. The GPIO pins for the relays and programmable LED are as follows:
- Relè 1: GPIO32
- Relè 2: GPIO33
- Relè 3: GPIO25
- Relè 4: GPIO26
- Programmable LED: GPIO23
After initial programming via UART, Over-The-Air (OTA) updates can be configured for wireless code uploads.
Video 1: Un overview of an AC/DC power supply ESP32 development board, demonstrating its programmable features. This video is provided by Aceirmc US.
5. Istruzioni per l'uso
Once programmed, the ESP32 module will execute the uploaded code to control the relays and other functionalities. The relay indicator lights will show the current state of each relay (ON/OFF).
- Controllo senza fili: Utilize the ESP32's WiFi capabilities to integrate the module into your smart home network. This allows for remote control of connected devices via a smartphone app, web interface, or home automation platform.
- Controllo manuale: The programmable button can be configured in your code to trigger specific actions, such as toggling a relay or changing modes.
6. Manutenzione
To ensure the longevity and reliable operation of your module, follow these maintenance guidelines:
- Mantenere asciutto: Proteggere il modulo dall'umidità per evitare cortocircuiti e corrosione.
- Pulizia: Mantenere la scheda pulita da polvere e detriti. Utilizzare una spazzola morbida e asciutta o aria compressa per la pulizia. Evitare detergenti liquidi.
- Temperatura: Utilizzare il modulo entro l'intervallo di temperatura specificato. Evitare temperature estreme, sia calde che fredde.
- Maneggiare con cura: Avoid dropping or subjecting the module to physical shock. When handling, minimize contact with electronic components to prevent electrostatic discharge.
7. Risoluzione Dei Problemi
If you encounter issues with your module, consider the following troubleshooting steps:
- Nessuna spia di alimentazione:
- Verificare che l'alimentatore sia collegato correttamente e fornisca la tensione specificatatage (AC220V or DC5-30V).
- Controllare che non vi siano collegamenti allentati o cavi danneggiati.
- Relè non commutante:
- Ensure your code is correctly configured to activate the desired GPIO pin for the relay (GPIO32, GPIO33, GPIO25, GPIO26).
- Check the load connections (NO, COM, NC) for proper wiring.
- Verify the load's power requirements are within the relay's capacity.
- Problemi di connettività WiFi:
- Confirm the WiFi credentials (SSID and password) in your ESP32 code are correct.
- Ensure the module is within range of your WiFi network.
- Check for any firewall or router settings that might be blocking the connection.
- Programming Upload Failure:
- Ensure the correct board and port are selected in the Arduino IDE.
- Verify the USB to TTL adapter is functioning correctly and its drivers are installed.
- Check the wiring between the module's UART port and the USB to TTL adapter.
8. Specifiche
| Modello | ESP32-WROOM-32E |
| Volume di alimentazionetage | AC220V / DC5-30V |
| Canali di relè | 4 |
| Tipo di relè | Relè 5V |
| Relay Load Capacity | AC250V/DC30V @ 10A |
| Memoria Flash | 4MByte |
| Connettività | Wifi |
| Dimensioni | 93 mm (3.66 pollici) x 87 mm (3.42 pollici) |
| Peso dell'articolo | 0.48 once |
| Produttore | DORHEA |
| Data prima disponibilità | 23 agosto 2024 |

Figure 5: Module dimensions for planning and integration.
9. Garanzia e supporto
DORHEA products are designed for reliability and performance. For any technical assistance or inquiries regarding your ESP32 WiFi 4 Channel Relay Module, please refer to the seller's support channels on the platform of purchase. Keep your purchase receipt for warranty claims, if applicable.