PROJECT HIGHLIGHTS

• small (45mm x 46mm) easy to fit into typical 60mm diameter electric in-wall box
• easy to connect into electricity grid (3 pole N screw terminal so additional junctions in electric box are not needed)
• controlled by physical switches
• can work without gateway
• based on Atmega168/328 not on Arduino

DESCRIPTION

This device was designed to be installed in typical 60mm diameter in-wall box and to be controlled not only by MySensors network but also by physical switches. This device can work independently even if MySensors gateway is down.

CONNECTORS

• 3 pin for switch button
• 6 pin standard Atmel ISP
• 2 pin RX/TX for serial programming (GNS and VCC are on ISP)
• 6 pole screw terminal for AC connection

SAFETY

• AC clearance 2.5mm minimum
• AC-DC clearance 5mm minimum
• 250VAC varistor
• Thermal fuse
• Slow blown fuse

PCB DIMENSIONS

45mm x 46mm

CONNECTION DIAGRAM

ASSEMBY INSTRUCTION

1. Solder ATMega
2. Solder other components on bottom side
3. Solder NRF24L01
4. Solder fuses and varistor
5. Solder connectors
6. Solder HLK and relays
7. Connect ISP programmer (i.e. AVR USB ISP) ) and burn bootloader (8MHz Internal oscillator) fuses settings: low_fuses=0xF7 high_fuses=0xDA extended_fuses=0x06
8. Connect serial programmer (Rx,Tx,GND,+5V) and upload sketch
9. Connect +5V and GND to the board and check if everything is working properly
10. Connect AC mains

Caution: You should always disconnect AC mains before connecting the programer!

DISCLAIMER

If you order or use this you agree to and understand that the author is not liable for any injury or damage howsoever caused and that you use this PCB at your own risk. This is DIY and the author has not made any professional test. This product has not been marked with any certification marks and cant be guaranteed to compliance with any standards.

LICENSING

This product is licensed under the CC-BY-SA OpenHardware certificate. For more information please see https://creativecommons.org/licenses/by-sa/4.0/