Testing a smart weather station: is the Homematic IP Weather Sensor Pro any good?
If you don't use a weather sensor in your smart home universe, the data from a meteorological website is usually taken as a basis. This often results in anything but accurate data. I use smart home products by Homematic IP, which derive their data from the Open Weather Map. However, I don't want to use standard or average values from any measuring stations, but exact values from my immediate surroundings. According to Homematic IP, the Weather Sensor Pro makes it possible to feed my smart blinds and wall thermostats with detailed information about outside temperature, air humidity, rainfall and wind speed and to let them respond the right way. I've put the Weather Sensor Pro and all its functions to the test.
Unboxing and assembling
When the box arrived, I was amazed. It was bigger and heavier than I'd imagined: 3.6 kilograms and 57 x 37 x 15 centimetres. I assumed it wouldn't fit in my pocket, but I didn't expect it to be this heavy. So I was intrigued when I started unpacking it. Although some parts, the wind direction sensors and wind speed sensors, for example, are made of plastic, they look of high quality. The bars and the mast are made of stainless steel and also feel solid. The whole thing is packed up well and the individual components are protected with cardboard parts and safety adhesive tapes. The scope of delivery includes the weather sensor as well as three AA batteries, an Allen key and a user manual.
After almost three pages of warnings and two more pages of general system information, the instructions describe the first step of assembling the weather station. First the wind direction sensor is plugged onto the base station, which I lovingly refer to as the trident. An RJ45 cable is led from the base station through the socket of the wind direction sensor and plugged in. After this, the whole thing is put together again – including tightening the screws with the Allen key. Next up is the anemometer, i.e. the wind speed sensor. I put it on its tip on the trident and tighten the prepared screw. The sensors have to withstand quite a bit of wind to be able to measure it.
The rain sensor follows next. The collection container looks like a big plastic cup without a handle and with a funnel inside it. I first have to remove the safety tape over the actual rain sensor, check if the counter rocker works, put the collector funnel over the sensor and then close it with a half turn. The wind speed and wind direction sensor are the only parts that require screwing, everything else interlocks with half a turn or with clips. Will it withstand strong wind? I'll find out when the next big storm hits Zurich. Finally, I put the three steel tubes together on which the Weather Sensor Pro is mounted and rammed into the ground. Or, as in my home, tied to the balcony railing with cable ties.
Switching it on and integrating it into my smart home
That's the hard part done. In my experience, teaching in and integrating it into the Homematic IP smart home universe happens almost automatically. The manufacturer is particularly proud of this. I open the battery compartment on the weather sensor, insert the batteries and the teach-in mode is activated. An orange flashing LED indicates that I have done everything right so far. The Homematic IP app on my mobile phone confirms this. I select «Teach-in device» and after a few seconds, the weather station appears. All that’s left to do now is identify it using the last four digits of the product number and the weather sensor is ready for use.
One small, but important detail is missing: aligning the device. I need to teach the Weather Sensor Pro where north and south is. I take a compass – a digital native, I choose my iPhone compass – and align the weathervane so that it is pointing north. Then I open the battery compartment and press the system button until the system LED flashes orange. I press the system button and the green light of the System LED confirms the northern alignment.
Now it's time to get down to business: embedding the weather sensor in my automated smart home commands or creating new processes. I've already programmed an automation that shuts the blinds, as soon as it gets warmer than 24 degrees in the bathroom. The other relates to the underfloor heating I've set the smart wall thermostat to maintain a constant temperature in winter and warm up slightly for a few hours in the morning and evening, as my partner and I are at home and like it to be a bit more cosy. We won't be using this anymore soon, as the heating is switched off in summer. That's why I'm working with automated blinds for the moment.
Functions and potential
How to create actual added value by integrating the Weather Sensor Pro in my Homematic IP universe? My first idea: I want the blinds to open if there's strong wind, to protect them from possible damage. After a few clicks in the app, the process is complete: as soon as the wind speed sensor measures more than 30 kilometres per hour, the blinds open. All I need to do is select a trigger and an action. I can also add an additional condition if I want to. In the example just mentioned, the trigger is the wind speed and the action is the opening of the blinds. Another automation I save is that the blinds close as soon as the outside temperature reaches 25 degrees Celsius or more. I select the thermometer of the weather sensor as the trigger and closing the blinds as action. I then add the condition that the process only starts if it's not raining.
If I had other smart home products, I could do a lot more with the Weather Sensor Pro. From airing the house via automatic opening and closing of windows to controlling sun blinds and indoor and outdoor lighting – the Homematic IP universe has almost no limits. The Weather Sensor Pro has a frequency range of up to 400 metres, so you don't need to place it directly in front of your home. It measures temperatures from minus 20 degrees Celsius to plus 55 degrees Celsius. Minus 20 doesn't seem much, but then again, when was the last time temperatures of -21 degrees Celsius were measured in Birmensdorf? Wind speeds of up to 200 km/h can be recorded and rainfall of up to 966 mm. Hopefully, I'll never experience reaching these two maximum values either.
Conclusion: an expensive upgrade for smart home fans
The Weather Sensor Pro is the perfect addition to any smart home that uses Homematic IP products. It's robust, quick to assemble, well explained and works from the get-go. Integrating it into the Homematic IP app and adding it to existing or creating new automatic processes works perfectly. The output data seems to be correct. As I couldn't get my hands on professional measuring instruments, I had to compare and verify the data with the help of commercially available thermometers and hygrometers as well as online data from weather sites. I'll make more exact measurements as soon as possible.
If you're converting your home for a smarter future, don't want to rely on Open Weather Map data and don't mind spending some money, I highly recommend the Weather Sensor Pro. If you're experimenting with smart home products for fun or have just started automating your home, I wouldn't recommend buying it. Why not? Firstly, it's too much money to spend for fun, and secondly, you can get by with the Open Weather Map data when you're starting off.
My next article will be a review of either smart sockets or window/door contacts by Homematic IP. If you don't want to miss this review and other smart home articles, follow me by clicking on the «Follow author» button on my profile.