Help wanted choosing the right board for home automation

Projects Discussion and Showcase Home Automation
1

Hi.

I am based in the UK. I have no knowledge of Arduino products but did some basic programming 40 years ago. I have a reasonable understanding of electrics.

I am interested in home automation. I want a system that is not held in the cloud, but maybe instructed via a mobile device so capable of internet connection. The system would need to be able to support a display screen on a wall.

The system would need to be able to support multiple sensors and relays for heating, lighting, and electrical systems and so on.

So here goes with my very very very basic questions...

Is an Arduino board the hardware?
Do you programme the hardware via a PC?
Can you connect hardware to the Arduino using physical cables?
Can you connect hardware to the Arduino using wifi?

and finally which board would be best for my project?

Thank for your help

Marvin

2

Yes, yes, yes.

Not all Arduino have WiFi capability.
But yes, you can connect hardware via WiFi, but you will probably need a processing board of some kind at both ends.

I don't think anyone can give you an accurate answer to that at this stage.

You might need multiple, WiFi-enabled boards, for example.

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4

Take a look at home assistant. You'd need at least a Pi though.

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5

Hi @PaulRB

Thank you for your help.

Perhaps I could dig a little deeper...

Re-reading I realise my wifi question was badly written. What I meant to ask is: Can I send and receive info to/from the board to/from my mobile? Not coding but like checking up what's happening? For the avoidance of doubt I hope to hard wire all physical devices to the board/s. ( I assume this means I will need the right amount of connecting points...)

Can boards talk to each other. i.e. can board A send and receive data from board B and vise versa?

What voltage does a board use? AC or DC?

Finally what information would help people to suggest the board setup I require?

Thanks again for starting me off in the right direction.

6

Thanks for that @wildbill.

I think that Home assistant goes a little further than I want to. I had read it up a couple of hours ago and it looks great for someone who wants to know everything, but I'm just trying to make several systems in the home work together.

Once the systems parameters are set they would rarely be changed. I don't need wifi connection except if its needed to code the board.

Thanks for sharing because I learnt what a Raspberry Pi was. :joy:

Marvin

7

First, I always recommend choosing one of the existing Home Automation Protocols.

It's really difficult to build something like a switch (or dimmer) that fit in a regular electrical box to replace an existing switch, works without re-wiring, and works remotely or manually, etc. And if you want to add another switch or controlled-outlet some time in the future you can just buy/order it. You don't have to build it.

I have a "simple" Z-Wave home automation system with a programmable hub-timer and about 10 controlled lights & outlets. I say "simple" because I can't access it remotely over the Internet or cell phone network.

I chose Z-Wave because at the time, a couple of years ago, when I upgraded from my antique X-10 setup there was more Z-Wave stuff available than anything else.

The big companies seem to have standardized on Zigbee but I'm pretty sure my Z-wave hub can communicate with Alexa, or Siri, or whatever, if I wanted to set it up.

The only thing I built myself is a "wake-up system" that fades a light up in the morning, and then beeps gently. It plugs into a controlled outlet and the hub is programmed to turn it on 5-days a week. The part I built doesn't have a clock built-in.

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8

Build your code and use the Raspberry Pico-W as your main microcontroller.
Then use Pimoroni Pico DV Demo Base - RP2040 DVI Multimedia Board - PIM588 where u can connect a TV to the Pico-W via a HDMI cable.

Yes, I know this is an Arduino forum, but from your msg, it looked like you might appreciate being suggested other more viable options outside the Arduino world. lol.

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Hi @DVDdoug

Thanks for the info. This has added to my knowledge.

For clarity I think I need to indicate the scope of the proposed automation.

10

Hi @Mars-Sojourner

Thanks for the info. This has added to my knowledge.

For clarity I think I need to indicate the scope of the proposed automation.

11

Thank you @PaulRB , @Wildbill, @DVDdoug and @Mars-Sojourner for your help!

Oh dear! I think I need to point out that I have realised that the systems I want to automate are obviously not typical. They are also existing but are using lots of complex wiring and relays. Just gaining the information that I have, I realise I do not want to control the system over the internet.

An automated home system means to me, that items would turn themselves on or off depending on preset permeameters. Having info/control constant to my phone would be information overload for me! :laughing:

I need to control various items based on wind speed, air temperature, air flow, humidity, sunlight, daylight, electrical energy use, electrical energy production, battery charge rate, water storage, water demand, heating, cooling, hot water, car charging, on grid and off grid energy supply, time of day and time of year.

The building already has several of these systems working, but I have achieved this the old school way with lots of complex relays and wires.

I am now looking at upgrading the system, so before I start I thought I would try to enter into 20th Century technology.

Relay box
Relay box1920×1440 421 KB
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The picture shows the switching for the hot water, energy storage, heating choices and car charging pre-set alternatives but needs to include further controls.

As the house uses 230vAC and 12vDC I need to understand what voltages a typical Arduino system uses and where the position to change from low voltage to higher voltage would be. Can anyone point me to where I should post such questions please.

Thanks again

Marvin

12

How do you currently get all these data items?

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The older (Original) Arduinos are typically 5V. The more modern ones are usually 3.3V. There are also similar products like the Teensy and ESP32 that are far more powerful and have more memory. These too tend to be 3V3. They may be overkill for your needs though.

Another important consideration is how many pins you'll need on the Arduino for I/O. The Mega has loads, the Uno, not so much.

For changing voltage, it looks like you're already using relays. You will need some that are switchable by 5V or 3V3 depending on your microcontroller. MOSFETs could be used instead for longer life.

For inputs, you'll need to condition the voltage down to what the controller expects.

14

Hi @wildbill

I don't have all the equipment to monitor these sets of data as yet and I expect to have to change what I am using.

Reading through various items I noticed that you can link items through blue tooth. Do the typical hardware items use DC?

Presently I can monitor air temp inside, air temp outside, humidity, electrical energy production, battery charge rate, volume of water stored, heating, cooling, hot water, time of day, indication when there is power going to the grid, voltage, and that's about it.

In order of the above list: digital thermostats, digital humidity stat, Inverter, another inverter, float switch,digital thermostat, digital thermostat,digital thermostat, digital clock relay, LEDs, digital voltage reader.

Here's a typical thermostat: (the one on the hot water tank)

Digital thermostat
Digital thermostat1920×2560 241 KB

I'm hoping to set up sunlight sensors, daylight sensors and time of year clocks, plus wind speed sensors and rain fall sensors. Not so much for accuracy as so much for example: yes its day light or no its dark for example. I don't need to know the exact lumens.

I am hoping to add the rest. Not every sensor needs to be completely accurate to be suitable for my purposes.

Installed in the house is an air source heat pump (ASHP), Photovoltaics (PV), 12v Battery storage, whole house mechanical ventilation with heat recovery (MVHR), Electric Vehicle (EV) charging point, solar diverter (diverts unused energy into heating the hot water before sending excess to the grid). Also there is rainwater harvesting, and an energy storage system that comes on over night or when the mains is off which is in development.

The above is simplified information.

One of the things that has occurred to me is that each sensor will probably need to be powered, even if it uses Bluetooth technology to transmit data, is this right?

If so how do people set up a sensor at one end of the house and a board at the other both using low voltage power? Two sources?

I noticed that you have a lot of experience in this field so I would be grateful for any advice.

Thanks once again

Marvin

15

Thanks for all this. I'm way way behind you in understanding.. I even had to look up what I/O was :flushed:

As my brother would say, the devil is in the detail...

Quite a few of the relays i would use would need to relay 230v 13amp power...

At present I expect the board would need to be a Mega, however I was wondering about running the work through more than one board. Can one board Bluetooth to another board?

After thinking further....

I can see that I'm well in over my head. I know I am an impatient person. I have looked at all this once before and been put off, however, I really want to do this. I think I'm going to look at a lot more videos and understand a lot more before attempting this.

Any pointers to good places to learn appreciated

Marvin.

16

There is one warning that rightly always appears in these threads. I'll do it this time:

Don't do anything involving mains voltage unless you know what you're doing.

There is another serious caveat here - your system sounds quite complex and coding is hard. You will likely be unpleasantly surprised by the number of bugs you can fit into a little program. Obviously, this matters a lot from a safety perspective if you're switching high voltage and/or current systems.

I would be inclined to build out a system that simply monitors and displays what's happening. When that works, you can consider control logic. Initially perhaps, just use LEDs to simulate your real systems.

For communications you can use wifi, bluetooth, zigbee or even LORA. I use wifi because it was convenient at the time of my build. However, in an English building, you may find that brick walls make wifi reception spotty. A mesh network like zigbee may suit you better in that case.

One of the folks on the forum wired up his house with over sixty nodes to control light switches and systems. IIRC, each node had a wifi capable ESP controller. I quite like that idea in your scenario - one master controller that talks to the sensor nodes and either switches stuff itself or orders the remote units to do it.

Wifi is nice because you can build a web page on your master device that your phone can access. Whether it's display only or allows overrides or parameter changes is up to you. Note that the minute the mark one is done, you will dream up new features for it :smiley:

Since your code is initially going to be buggy (live with it!) you will be well served by adding some logging to see what the sensors say and what the controller did and when.

Some of the ESPs can partition some of their memory as disk for storing such things, but personally, I'd push logs to something separate with plenty of space. You can use MQTT and have a logging channel that something else stores. If you have a PC running all the time, that could take care of it.

You will need to consider how your system deals with failures. What if the power goes out? What if your controller or a sensor node crashes. What if your logging fills up its space? What if one of your sensors is giving bad data.

To model all this bad news, I'd be inclined to build a simulator to exercise the controller. You can of course use an Arduino to do this.

Really, it's all enough to want you do it old school as you have it now :wink:

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17

Hi @wildbill

I heed your warnings and good advice. Thank you for taking the time to reply in depth and share your knowledge. I know how long these things take.

Most of the work in my design so far has been for fail safe protection. I have had quite a few challenges setting up what I have running so far, and yes your right, it is complex.

After your last post I researched C++ coding and it feels like an upgrade of what I was using in 1984.

I already have LED indicators to show what is going on all over the place: We're on the same page on that one as well!

The reasons I used hard wire in the first place was because I wanted to keep the systems off the internet, was not sure of WIFI reception throughout the building because the building is wrapped in Polyurethane Insulation Material which is faced with foil and didn't want to commit to one brand or internet control.

The arrogant side of me says I can build a system that will work. However the price I would pay of my time over the next 2 years in taking down the system I have whilst building up the new one is one hell of a mountain to conquer.

Hahahahaha!!! I'm on mark 6 already!

Yes it is. :frowning_face: A friend of mine says every day is a school day.