This MCP23017 Relay Shield Arduino Micro I²C relay controller was designed to function as a relay shield for Arduino Micro.
This controller consists of 24 DPDT relays rated at 5 Amp at 120VAC or 5 Amp at 24VDC. Three groups of 8 relays on this controller service all 24 on-board relays using dual MCP23017 GPIO interface processors. The first MCP23017 Relay Shield Arduino Micro control the first 2 groups of 8 relays using GPIOA0:7 and GPIOB0:7. The third group of 8 relays is controlled by the second MCP23017 interface processor using GPIOA0:7, while GPIOB0:7 is reserved for user-programmable digital input/output (accessible using the on-board screw terminals).
Controlling relays is easy, simply set the associated GPIO port to Digital Outputs. Next, set the on/off state of each output the associated GPIO port to directly control the 24 on-board relays. Twenty-four LEDs indicate the status of the 24 on-board relays.
The relays on this controller are rated for low-power signal switching applications, offering an ideal choice for telecommunications, audio, low-power signal, and other resistive or low capacitive load applications. The relays used on this device are Double Pole Double Throw. DPDT Relays consist of two separate switches that change position simultaneously. External devices may be wired to turn on when the relay turns on. Optionally, external devices may be wired to turn off when the relay turns on.
This relay should not be used in inductive applications (power switching applications involving motors or transformers of any kind).
This controller includes an on-board I²C expansion port, allowing an easy pathway to expansion for controlling more relays, reading sensors, or expanding to any I²C device we develop in the future. Up to eight MCP23017 based devices may be connected to a single I²C port. This controller counts as two MCP23017 Relay Shield Arduino Micro on the I²C bus. The start address of this device is set using 2 on-board jumpers. Up to four 32-Channel controllers are supported on a single I²C bus.
This relay shield is also compatible with a 418MHz Key Fob receiver (Part Number: MKFR), allowing your Arduino Micro to receive and process remote Key Fob commands up to 750 feet away. Up to 40 remote controls may be associated to the MKFR. Program your Arduino Micro to control relays in any way you can imagine through the use of a remote Key Fob. Compatible with 1, 2, 3, 4, 5, and 8-Button MS Series Key Fobs from Linx Technologies.