Garden Lighting

The Goal was to surround the garden perimiter in fairy lights and for home assistant to switch them on/off at sunrise/sunset.

The Solution

1. microcontroller - logic gate for switching the lights on/off
2. MQTT - allow fast messages to/from the controller
3. Power Relays - allow switching of power on/off

microcontroller - PicoW

The rapberry pico w implements mqtt, and perfoms simple pin up or down, based on the desired state from mqtt.

Power Relays

5V Power Relay allows control signals from the pico's 3v output pin up, to close the loop on a light circit.

and a buck boost convertor to step down the power from the shed.

Home Assistant

Home assistant can ping out to mqtt to turn the lights on with automations or with a button press

Christmas Time

At Christmas, I add a couple extra light strips which can use the same system, as the microcrontroller can contol up to 6 seperate light circits.

Lessons Learned

AC vs DC circuitry

When I purchased some extra lights for christmas, I figured any old ones will do... as everything is converted to DC before being powered... nope, AC christmas lights powered with DC current will only light half the lights in one polarity and reversing the current will light the other half.

I could have made some form of simulated AC alternating polatities, but this wouldn't have been efficient and probably would have been blinky. So the AC set remained for AC use.

Buying any christmas lights with a battery or solar pack will ensure it's a DC set.