Getting started with openHAB - basic hardware questions

Hi guys,

I’ve just started with openHAB and I was thinking of building my first project, but I’m running into some very basic hardware questions.

I was thinking of switching a light near the front door of our house using the sunset times.
So basically: when the sun sets, or preferably a half hour in advance, switch the light bulb on untill midnight and then switch off. I would love to add a motion sensor in the neighbourhood so if someone approaches the front door when it’s night and the lightbulb is switched off, it would need to go on.

This would be a first testcase for home automation. I have some future plans like adding automated sunscreens, central heating, …

I’m thinking of running openHAB on a raspberry pi (model 3, B+) but what else do I need?

  • of course a smart lightbulb (Philips Hue, Ikea Tradfri, INNR, Osram Lightify, …) and in second stage a motion sensor

So my questions:

  1. When I go with the Ikea Tradfri system (which has E27 and GU10 LED lights and motion sensors) do I need the Ikea Tradfri connection HUB?

I assume I would need this, so the same would be true for all other systems like Philips Hue …

  1. When I would go with a Zigbee compatible LED light, can I use a Zigbee USB Dongle in my Raspberry Pi?
  2. When I would go with a Z-Wave compatible LED light, can I use a Z-Wave USB Dongle in my Raspberry Pi?
  3. When adding other systems, like Somfy sunscreens, I would need their bridge? (the more systems I add, the more bridges I would need)

Thanks to get me started

Hi @Dinobe and welcome to the openHAB community!

Control of outdoor lights based on sunrise/sunset is actually how I started out my configuration, so I can tell you how I took care of it (of course, there’s tons of ways to do this, this is just one of them).

I used ZWave, specifically the Aeon Z-Stick (Gen 5 is the latest and recommended version) and a GE/Jasco Z-wave switch that replaced my original toggle. The benefit of using a hardwired swich as opposed to a hub + smartbulb is that you can keep easy manual control of the lights. The hub + smartbulb solutions win out when you start adding more lights to the system, since those ZWave switches aren’t cheap.

You can use the astro binding, with its multiple sunset/sunrise setpoints (civil, nautical, astro dawn/dusk) to adjust your on/off times for the light. A simple rule that fires on one of those events would turn the light switch ON, and another rule (based on cron set for midnight) would turn the light OFF.

As for your hub question, it’s true that you need a hub for every type of protocol your devices use (Phillips for Hue lights, SmartThings, IKEA, Iris, etc…), but openHAB has bindings for most of them already. Since you’re starting out, I would pick one protocol ot start with, and only add new ones when you need htem. ZWave is definitely a good one to go with, as there’s tons of devices on the market supporting it, including HVAC thermostats (I use the CT100), sensors, switches/dimmers, etc…

1 Like

Thanks Bartus, thats’s the simple answer I was looking for :slight_smile:

I will keep the wall switch permanently in the switched on position and let the light be switched by an openHAB rule. The light near my front door is a non-crucial light, my daily comfort will not be impacted by it’s functionality.

Right now I see it more as a test case and a nice-to-have feature. When it isn’t working nothing is lost.

So needed:

  • Raspberry Pi + openHAB software
  • Z-Wave usb dongle
  • Z-Wave compatible light bulb

Optional:

  • Z-Wave motion sensor
  • Z-Wave wall switch.

If you already own the RF control part and want to keep using it, well yes you will need some sort of bridge.
If you do not, the cheaper and better alternative would be to add ZWave actuators to every roller shutter or sunscreen as you already run the ZWave gateway (USB stick) for lighting.

ZWave is a good choice particularly for existing lights and if you want to extend your home automation beyond lighting, just these bulbs are hard to get hold of (they exist but very few choices and rather expensive, plus think what if your bulb is breaking).
There’s also E27 fixtures to include zwave control (so you can at least replace the bulb independent from the zwave part), but the most common approach is to place small actuators into your wall, below your wall switches. These you can wire both to, your light and your switch, but you don’t have to connect the switch if you just want to control the light from openHAB.

That’s an interesting approach which I had not considered. So I can use any old lightbulb but make them work by triggering the wall switch.

I’ll have a look into that…

Something similar for a wall plug would be doing this: https://www.youtube.com/watch?v=fzh2qza_I2k

Yes and that would even keep working if openHAB was down.
And you’re not limited to lights. I’m also using these for all of my HVAC automation.

Yeah that’s right thos actuators I was referring to, you can connect anything there.
There’s also variants to connect LED strips, 12/24V devices and dimmers.

Status update:

I got myself an Raspberry PI 3 with Openhab2 installed, an Aeon Z-Wave USB stick (Gen5) and a Fibaro double switch.

The Raspberry with Openhab is already up and running, I need to check if the Z-Wave stick is working correctly. My raspberry sees 2 sticks: one at /dev/ttyACM0 and one at /dev/ttyAMA0.
(One of them gives a connection error, one seems to be online)

I don’t know what happend exactly, I’ll need to investigate.

The Fibaro double switch module needs to be build in the wall switch. (todo). The fibaro unit is thicker than I estimated. I hope it fits behind the switch.