8-Channel 433MHz RF TTL Serial Relay Module Board DC 5V

8-Channel 433MHz RF & TTL Serial Port Relay Module — DC 5V

Take full command of your automation projects with this versatile 8-Channel Serial Port Relay Module. Designed for makers, engineers, and electronics enthusiasts, this board combines 433MHz RF wireless remote control with TTL serial communication to give you flexible, reliable switching across eight independent relay channels — all from a compact 128 × 48 × 16 mm form factor.

Whether you're building a smart home controller, an industrial automation panel, or a DIY electronics project, this relay board delivers the multi-mode control and cascading capability you need to get the job done right.

Key Features

• 8 High-Current Relays: Each relay supports up to 250V / 10A, providing strong driving capacity with individual LED status indicators for at-a-glance monitoring.
• Dual Control Interfaces: Operate via TTL serial port (UART) or 433MHz RF remote control — giving you both wired and wireless flexibility.
• Four Versatile Control Modes:
  • Self-Locking Mode: Toggle a relay on or off with each button press (remote & TTL).
  • Interlocking Mode: Activating one relay automatically turns off all others — ideal for mutually exclusive switching (remote & TTL).
  • Point Action (Jog) Mode: Relay stays active only while the remote button is held down (remote only).
  • Round-Trip (Timed) Mode: Relay opens on command, then automatically closes after a set delay — default 3 seconds, configurable up to 65,535 seconds via serial port (remote & TTL).
• Cascadable Design: Chain up to 8 boards together to control a total of 64 relays from a single interface.
• Built-In Protection: Overcurrent protection and reverse connection protection safeguard your circuitry and connected devices.
• Flexible Power Input: Powered via USB Micro connector or screw-type terminal blocks — your choice.
• Normally Open & Normally Closed Contacts: Supports both NO and NC wiring configurations for maximum circuit design flexibility.
• Configurable Settings: Baud rate, module address, working mode, and power-restoration state are all readable and settable via serial port.
• Power-Off Memory: Optionally restore relay states after a power cycle, ensuring consistent behavior on restart.

Specifications

What's in the Box

• 1 × 8-Channel TTL/433MHz RF Relay Module Board

Note: Due to lighting and display variation, item color may differ slightly from images. Please allow ±1–10mm tolerance due to manual measurement.

For general guidance on safe wiring and relay circuit standards, visit the U.S. Consumer Product Safety Commission (CPSC) for consumer electronics safety information.

Frequently Asked Questions

Q: Can I control this 8-channel relay module wirelessly without a computer?

A: Yes! The board includes a built-in 433MHz RF receiving module, so you can control all 8 relay channels using a compatible 433MHz RF remote control — no computer or serial connection required. The remote supports Self-Locking, Interlocking, and Point Action (Jog) modes.

Q: How many relay boards can I chain together, and how many relays can I control in total?

A: This relay module supports cascading of up to 8 boards. Each board has 8 relay channels, so you can control up to 64 relays in total from a single TTL serial interface — perfect for large-scale automation projects.

Q: What happens to the relay states if power is lost and then restored?

A: The module supports power-off memory functionality. You can configure it to either restore the previous relay states after a power cycle or return to a defined default state. This setting is configurable via the TTL serial port, giving you full control over behavior after power restoration.

Q: What is the default baud rate and can it be changed?

A: The default baud rate is 115,200 BPS. Both the baud rate and the module address are fully configurable and readable via the TTL serial port, allowing easy integration with a wide range of microcontrollers such as Arduino, Raspberry Pi, ESP32, and more.