Please, proceed carefully following the tips published in this blog, specially when Main Power is involved. I'm not responsible for any damages caused by what is written in this blog.
Thank you

Friday, 26 October 2018

Home Automation System - Automating a floor lamp

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

Friday, 5 October 2018

Home Automation System - Two PZEM-004T and a single ESP8266

After my successful experiments with the PZEM-004T and a Nodemcu ESP8266 aim to monitor power consumption (devices are actually working well in my ground floor power monitoring system, see https://domoticsduino.blogspot.com/2018/05/home-automation-system-energy.html), I decided to update my photovoltaic production monitoring system, actually based on a Wifi 433Mhz receiver (see https://domoticsduino.blogspot.com/2017/08/home-automation-system-mqtt-and-rf433.html).

Actual system has a problem due to an invalid read of power values when the inverter is switched off. In fact it gives me about 250W power production...

My idea is to use the same devices used for the ground floor power monitoring system...so a PZEM-004T and a Nodemcu ESP8266.

These are the devices:



Because my inverter is near the electrical panel in the garage, I decided to let the things more complicated adding another PZEM-004T to also monitor the basement consumption with the same ESP8266.

Then I added also a temperature and humidity sensor to the same circuit.

My following step was to check that a single NODEMCU ESP8266 was able to control both PZEM-004T...My tests were successful

Here is it my first PZEM-004T linked to the main output cable of the inverter...on the right you can see the DHT11, temperature and humidity sensor (it's a not so accurate sensor, but it's right for my kind of measurement...)

This is the second PZEM-004T, linked to the main cable of basement power, inside the electrical panel

Complete view:

Now it's time to write the software and test it.

I decided names for the MQTT topics and I created items and sitemap objects for OpenHAB

This is what we could see in my OpenHAB BASIC UI

Energy Consumption value is the sum of all the sensor power (2 of them are already running)
Values are different related to the previous screenshot because they continuously change

Last step: I created some charts in the Grafana dashboard

My primary target was reached: my production monitor give about 0W when the inverter is switched off