Skip to content
MKk
←All workCase study 08

A 4-channel ESP32 controller that installs behind an existing switchboard.

Role
PCB & firmware design
Year
2025 — now
Type
Hardware
Status
In progress
Repository↗
ESP32K1K2K3K4230V ACISOLATEDPCB-01 · SMART SWITCH · REV A

Overview

4

Channels

16 A

Relays

230 V

Mains, isolated

2

Ways to switch

01

Most smart switches ask you to rip out your switchboard. This one sits behind it. Optocouplers sense the existing wall switches, so they keep working, while the ESP32 adds Wi-Fi control from an app — either one can switch the load.

The board isolates the 230 V mains side from the logic with an AC-DC module, switches loads through 16 A relays, and protects everything with a fuse and surge suppression — laid out as a multi-layer PCB in KiCad.

What’s inside

  • Dual manual + Wi-Fi control
  • Optocoupler switch sensing
  • AC-DC isolation
  • Fuse & surge protection

Built with

  • ESP32
  • KiCad
  • Embedded C
  • Optocouplers
  • 16 A relays
  • AC-DC isolation
STEPS 1,284V 4.82 E 3.1 JPCB-02 · PIEZO HARVESTER · ESP32 MONITOR

Next project

Footstep Power Generation →

Turning footsteps into stored electricity, and measuring every one.