4 Channel Relay Hat Board For Raspberry Pi is one of the "docker pi" module.
It has a 4-channel relay, it is the best choice for smart home projects.
This four-channel relay uses high-quality relay modules combined with the most popular microcontroller technology to communicate with the Raspberry Pi.
You can use multiple modules stacked together for use.
You can stack up to four layers.
Switch the I2C address of the device through the DIP switch on the circuit board to ensure that the four-layer module gets different addresses, thus avoiding the problem of address duplication.
The module is very fast, easy to install, and supports multi-language development, making it ideal for smart home projects.
NOTE: The 4pin pin is a backup that supplies power to future products. You can ignore those pins. Please do not connect any device to that pins.
Easy to install
4 channel relay
Support I2C protocol
Support for stacking
Support multi-language programming
Support 3A 250V AC
Support 3A 30V DC
Support address switching by dial switch
Support relay status light prompt
Independent of the programming language, it only need I2C protocol support
You could use the command control directily instead of programming
Use the raspberry pi to replace the trandition switch
Compatiable with multiple protection board
1 * 4-Channel Relay Hat Board
4 * M2.5x11+6 copper stick
8 * M2.5x5 screws & nuts
1 * Instructions