Let's continue with my
Home Automation System design, based on the wonderful
OpenHAB
This time the main
attraction is a simple floor lamp that will be trasformed in a
SMART Device, using a
Sonoff Basic.
These are my
soldiers:
For those who don't know it,
SONOFF is a simple "wifi button", which allows you to control electrical loads remotely. The
Basic version is the simplest one with a single relay.
It seems a simple job...
I will replace the standard button with the
SONOFF...so, I will cut the wires to move away the button from the lamp...and plug these wires in
INPUT e
OUTPUT pins of the
SONOFF.
Let the things be a little more complicated: on
TASMOTA (https://github.com/arendst/Sonoff-Tasmota/wiki/DHT11-Wiring---Sonoff-Basic), I learnt that it's possible to manage an humidity/temperature sensor, linked to a free pin inside the SONOFF (GPIO14). A compatible sensor is the DHT11 and, luckily, I own some of them.
This sensor has 3 pin,
Vin, GND and OUT. So I link Vin and GND to the right SONOFF pins and OUT pin to the GPIO14 (always inside the sonoff)...To discover the right position of these pins, I used again the TASMOTA Wiki (https://github.com/arendst/Sonoff-Tasmota/wiki/GPIO-Locations)
Here are the wires soldered and protected by a heat-shrinking sheath
Now, I have to solder the other side of the wires to the DHT11...
Also here I used a
heat-shrinking sheath ...these pins are very close
And here is the complete device...
Now I make an hole in the plastic case to let the wires get out
And here is the lamp with the SONOFF and the DHT11...
Now it's software time.
Using the well known
TASMOTA web interface, I selected the right sensor connected to the
GPIO14.
and then I inserted the usual
MQTT informations.
Back to the home page, I noticed that the data acquired by the
DHT11 is displayed on top of the page
Let's configure OpenHAB defining new items and the MQTT topic used by the SONOFF...
My
MQTT topic will be
smarthome/light_env/%topic%/%prefix%/
Looking to the TASMOTA console, I noticed a new prefix in the topic related to the temperature and humidity information:
This will be the topic which I'll use in the items definition.
Here is the result
Basic UI
Grafana Dashboard
And this is the switch for the lamp
-----------------------------------------------------
Similar items used in this project
-----------------------------------------------------