M5Stack Single-phase AC SSR Unit (CDG1-1DA-10A)

M5Stack AC SSR Unit for Single-Phase Load Switching

The M5Stack AC SSR Unit combines an ESP32-C3 control board with a CDG1-1DA-10A single-phase solid-state relay. It supports local button control, I2C slave control, and Modbus networking, allowing the same hardware to fit bench testing, local machine control, and distributed automation systems.

The relay is specified for AC 24–480V load circuits with a 10A rated load current. The control side supports DC 3–32V input to the SSR, while the controller can be powered through Grove at 5V or through the RS485PWR interface at 9–24V. A programmable SK6812 RGB LED provides status indication.

Choose Button, I2C, or Modbus Control

Button mode supports direct local switching. I2C control uses address 0x50 and is useful when the unit is close to an embedded host. Modbus mode uses the RS485PWR interface for distributed systems; the documented communication configuration is 115200bps 8N1 with default device ID 0x0004.

Solid-State Switching Without Mechanical Contacts

A solid-state relay has no mechanical contact movement, which avoids contact bounce and mechanical wear. Thermal design still matters: on-state voltage drop produces heat, and the usable current depends on enclosure airflow, ambient temperature, load type, switching profile, wiring, and installation conditions.

Plan for the Actual Load Type

Resistive heaters, motors, transformers, and other inductive loads behave differently during startup and switching. Size the relay and protection devices for inrush current and fault conditions rather than only steady-state current. Verify the manufacturer's derating guidance for the final load.

Mains Voltage Safety

AC mains voltage can cause severe injury, fire, or death. Use appropriate fusing, creepage and clearance, protective earth where required, insulated terminals, a rated enclosure, strain relief, and installation practices that comply with local electrical regulations. Disconnect power before wiring or servicing. This module should not be used as the sole safety isolation or emergency-stop device.

Technical setup details are available in the M5Stack ACSSR documentation.