Home automation, Light dimming
May 15, 2024, 18:15
Hello, I'm looking for build a light dimming on my house, using a PIZero 2W or a PI4.
I searched for dimming modules, I found this product : https://fr.aliexpress.com/item/32802025086.html
"Dimmer 8A-400V" look good but I'm a bit afraid as it's a chines product, I wont burn my house <:CH_PepeWizard:704997748461535314> Did someone already tried this module / know another good module to make lights dimming ?
Note! Working with live voltage can be deadly!
And using such module with Raspberry Pi isn't ideal as the Pi isn't a real time OS and with that module you need to detect the zero crossing and then turn on the load and turn of it after desired time. and this has to be performed with milli second precision.
That module is more suitable for a Arduino and not as a beginners project.
I would NOT recommend that module as it is a live module.
I would recommend https://itead.cc/product/sonoff-mini/ or https://itead.cc/product/sonoff-basicr2/ or similar depending on where you will deploy it.
And replace the firmware with tasmota (https://tasmota.github.io/docs/) firmware and then you can control it with a Raspberry Pi via the MQTT protocol.
Many thanks for your reply, I’ll check all your link this evening, but about the Os I’m looking for use HomeBridge
HomeBridge is an application, the OS is "Raspberry Pi OS".
And HomeBridge can easily integrate with Tasmota devices among many others.
Okay thanks
The 2nd link is just a basic switch (ON/OFF) without dimming ?
Sorry, I think both are. My point is to use that type of module instead of the uninsolated module.
For basic switch I was looking for : https://www.kubii.com/en/modulos-reles/1974-4-channel-relay-module-24v-3272496008359.html
Those are uninsolated as well.
They say "24V", but on the board it's written 250VAC/10A
What do you mean by "uninsolated" ? The primary and secondary can connect ?
The PCB is uninsolated
VCC: Module supply voltage 5V / 12V / 24V
The relay coil is a 24v, but there is 5v available
Oh that's not a big deal, I will put the board into a safe box
Ok if you feel confident
And Rasbp deliver 5V DC
So I think it should be good
Then I would suggest you use a "Wemos D1 mini" as a controller for the relays
Since it's selled by an Official Raspberry reseller, I hope it's enough safe to be used
The GPIO on the raspberry Pi is 3,3v
All ?
I was thinking some are 5 ðŸ˜
I just saw this but currently not tested
But some of the relay boards has drivers (transistors) that drives the relay and they can accept 3,3v
All GPIO is 3,3v
Hm
So my relai will not work 😦 because of VCC: Module supply voltage 5V / 12V / 24V
I need to find another one with 3,3
Or 5volt that can accept 3v on the Input.
Yes
What's are the 2 "+5V" GPIO pins ?
The GPIO 2 and 4
+5v is NOT GPIO
That is the 5v rail on the Pi
I think I need to read the whole pins doc, I missed so much points :c
And you can't use that to heavily and relays can create nasty votage spikes
GPIO = General Purpose In/Out
+5v is the 5 volt rail, 3,3 as 5v but 3.3vvolt
They supply power (Out) or 'read' signal (In)
+5 volt is static 5volt
and 3,3 the same
Okay got the point
and GND is the common ground
And then the GPIO can have special features as I2C, Serial, SPI
PWM also is a "special features" ?
And as I have suggested use a "Arduino" to control the power module, relay or TRIAC (dimmer)
Yes, as the special features demand more precise timing and such, than the OS cant make, aka Real time
As Arduino is not a computer, I can't use it directly with my HomeBridge, but maybe I can 'control' an Arduino using the Raspb ?
Arduino can have a firmware that can communicate over WiFi with HomeBridge
And the protocol is often MQTT
You recommand Wifi over cable ? (If I go for an Arduino, they will be in the same box)
So what I suggest is:
Raspberry Pi (HomeBridge) <-> WiFi <-> Wemos D1 with Tasmota - Relay/Dimmer
If you go with Arduino/Tasmota you can separate the HomeBridge and control many Arduino/Tasmota devices over WiFi scattered around the apartment/house
Hm I prefer your first suggestion I think
That is how I have built the automation in the apartment.
The advantage is that you separate the "live voltage" devices, the system is modular and eatch arduino/Tasmota device has a web page that you can control each device separately.
And I can say that there is a high probability that your Pi will crash.
What’s happen if the Raspb crash with Homebridge running on it ? The Arduino cards will change their states ?
No they are autonomous devices.
Hm that’s sounds good 🤔
Well more « safety »
Many thanks for all your tips regarding my requests
Example of the UI on a Tasmota/Arduino device. And there you can se the "Toggle" function.
Oh you have W consumption ?
Yes some of the "SonOff" devices has that feature
Not bad, for bulbs it’s not really useful as W consumption is very low for bulbs but it’s a nice to have
It is a "Nice to have" and it wasn't so much higher price.
For this example ? Do you have any references to advise for the Relay/Dimmer ?
I do not need a 10A switch, I'm using low consumption led bulds (Max 3 per Relay/Dimmer), I think a 1A should be good 🙂
10A is kind of standard.
Okay
Do you have any refs ?
Ref for what?
Relais / Dimmer
I don't understand?!
I mean good product references
I read the product datasheet when I buy stuff. So the answer is no!
okay 🙂
eBay and Aliexpress and similar has seller that come and go and sometimes they sell other products with same part no.
And for ready made products as sonoff, I buy products where the firmware can be changed to opensource based firmware as ex. Tasmota.
I dislike vendor lock in firmware.