The Ikea Slagsida is a under Cupboard Light with a touch sensor to turn it on/off with a 50% brightness step in between.
Specs on this lamp (60cm variant):
110-240V
6.6 W
warm-white
TYP L1616
Example offering:
I always thought turning multiple of those on/off was pretty annoying.
So here’s the howto integrate them into HA:
You’ll need:
- a DC to DC power supply (buck converter) which can turn 24 V to 5 V (or 3.3V - your choice). Make sure it can regulate the voltage.
- an Esp8266, like the Wemos D1 mini
- Some wire
- A soldering iron
- A knife
Disassembly
After disconnecting the lamp from power at the back side (four screws, a cap, a small plastic retainer bar), remove all small screws on this side.
You can now pull off the front side on the thicker side of the housing, then pull the front side towards the thin side. It should release easily (if not you might have missed a screw in the back).
The two side pieces might fall off in this process. But they are easy to put back into place when assembling again.
Below the front panel is the pcb inside a plastic housing. Release the housing with the two plastic clips and pull a bit towards the clips.
It should slide out on the other side. If not: You can release the third latch on the back if necessary.
You can now bent both parts of the housing away from each other by inserting a flat screw driver between. The front plate with the touch sensor should pop out with no issue.
Now release the power connection plug by prying with a screwdriver below it, and then (carefully!) do the same on the PCB.
Disconnect the old controller
On the board are two controllers, one is for receiving the touch input and sending the brightness signal and the other one will receive the dimming signal and power the LEDs.
The brightness signal is on the original controller 3.3 V, so we can easily replace it by an Esp8266 which will also output 3.3 V signals.
First we need to scratch away 4 connections on the PCB with the knive (cut marks marked in violet):
Solder new connections
Now you need to solder 4 wires to the original PCB. The 24 V and Ground connections will feed your DC-to-DC power supply. Connect the 3.3 V pwm to D2 on the Esp8266, the touch button to A0, the Vcc out from your the power supply to the 5V port and ground to G.
Program the Esp8266
Now plug your computer into the USB port and open ESPHome in your HA instance (with a webserial compatible browser, like Chrome).
Create a new configuration in the guide for a Wemos D1 Mini and extend the configuration like this:
output:
- platform: esp8266_pwm
pin: D2
frequency: 2000 Hz
id: pwm_output
min_power: 0.005
zero_means_zero: true
light:
- platform: monochromatic
output: pwm_output
name: "Kitchen Under Cabinet Light 01"
If you want to experiment with touch, try this:
sensor:
- platform: adc
pin: A0
name: "Touch Switch ADC"
id: touch_switch_adc
update_interval: 100ms
filters:
- multiply: 100
- delta: 3
switch:
- platform: template
name: "Touch Switch"
id: touch_switch
optimistic: true
globals:
- id: t_sw_bool
type: bool
binary_sensor:
- platform: template
id: touch_switch_pressed
name: "touch switch pressed"
lambda: |-
if (id(touch_switch_adc).state > 1) {
if (id(t_sw_bool) == false){
id(touch_switch).toggle();
}
id(t_sw_bool) = true;
return true;
} else {
id(t_sw_bool) = false;
return false;
}
Source for the analog port touch code:
You may need to adjust the dead zone by raising or lowering the delta-filter.
I’m not using the touch buttons, but using a delta of 10 and touching the bare metal worked flawlessly for me. Haven’t tested it with the enclosure around it, though.
