The Relay Expansion board aims to expand the interfaces of the Raspberry PI adding 16 new GPIO outputs which can be easily connected to the Relay boards. This board can be used with commonly available 8xRelays boards for any automation project involving the Raspberry PI. The Board contains one MCP23017 chips for the GPIO expansion, the address of the I2C is configurable within the range 0x20 to 0x27 using the 3 jumpers. The Board is compatible with the open source Hydrosys4 Software to create more scalable irrigation and automation systems.

Regarding the Hydrosys4 software you can check the following link: Hydrosys4 project

What is in the package:

The package will include the board as in the picture. There might be some differences in the color and position of the components that will not affect the described functionalities.

Options:

Additional Hardware can be ordered using the options in the upper-left corner of this page. (e.g. the 8 relays board)

The Hardware:

The board includes the following parts:

• 2x Connectors for the Relay: To connect the 8xRelays boards
• 3x I2C connectors: Can be used to connect to Raspberry or to connect other expansion boards
• 3x Jumper connectors: Changing the position of this Jumpers is possible to change the I2C address of the board. If ADD0 is connected to GND it's value is Zero, if it is connected to +5v then its value is 1, the same for the other two addresses. When all the addresses are at Zero, the I2C address is 0x20, when they are all to 1, then the address is 0x27.

The board can be connected with 5Vdc Relays boards which are commonly available, see below picture.

The Relay board have to have:

• 5V dc power supply
• As in the below picture, the GND should be on the left, the VCC should be on the right.

The Software

The board is compatible with any software which supports the following chip: - MCP23017 (for GPIO expansion)

The board is compatible with the Hydrosys4 software which is specifically designed for the Irrigation and environment control. Below a screenshot of the SW:

To install the Hydrosys4 Software you can refer to the following link: SW Installation&Setting

Are you able to build it?

IRRIGATION AND AUTOMATION USING THE HYDROSYS4 SW With the Hydrosys4 SW, the system can be implemented even for non technical people, it does not require experience with Raspberry PI, programming and electronics, you need just a little bit of knowledge of how a relay switch works. In any case, this video might give some useful info: Relays and Valves connection

For more advanced users, any Software that is compatible with the chip MCP23017 can be used. The board can be a great tool to implement automation projects using the Raspberry PI and a variety of SW for automation.

Documentation

There is a dedicated website and some youtube videos with step by step guide.

For More info you can refer to:

Youtube: Hydrosys4 installation and Connection

Youtube: Valves&Relays connection

For more info you can refer to website: Hydrosys4 website

Forum: Hydrosys4 Forum