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RelAC

HomeKit 2-channel Relay module with mains Switch Input based on the HomeSpan library. It is mainly intended to be used with mains voltage appliances controlled in parallel with the Home app and physical switch. It could be hidden e.g. behind a wall light switch.

Main Features

• Mains Supply 100-240 Vac
• Status LED and Control push button for easy configuration
• 2 latching relays for low power consumption and thermal emmisions
• 2 live inputs
• Small form factor to be hidden behind the wall light switch.
• Can be configured as single channel device to save cost

Switching Relays

• High quality, low wear Panasonic ADW1203HLW
• Switching Capacity 16A @ 277V AC
• Contact material AgSnO2 to minimise arcing

User Integration with HomeSpan

Status LED and Control Button are attached to deafault pins for most of the boards. S1 Button is also used as boot button during programming

• LED GPIO2
• Button GPIO0

Pinout

Pin assignment for relays and switch inputs. For single channel version only RELAY 1 and SWITCH 2 are used.

• RELAY 1
  • on GPIO27
  • off GPIO26
• RELAY 2
  • on GPIO33
  • off GPIO32
• MAINS INPUT
  • switch 1 GPIO16
  • switch 2 GPIO13

User Guide

The setup procedure and configuration can be found here

To Do

• finish 3D printed case
• reduce footprint with next revision
• change layout of programming pins and add RTS support