Xiaomi Aqara Zigbee Shock Sensor
Installation via the Homey:
You can use this sensor directly without the Xiaomi Gateway. This is of course very nice if you do not want to send all your data to China. To add it, log in to the Homey and go to your devices. Then click on the plus sign and look for the Aqara Vibration Sensor. If you do not have the APP then you must install it.
To start adding, press the button on the bottom for 5 seconds. The LED will blink blue. Then keep pressing the button every 2 seconds to keep the sensor awake. Continue to do this until it is completely added by the Homey. I see the sensor appear and the opening / closing of the door is registered. The only thing missing is the battery status. Make sure you keep the sensor close to the Homey. I have noticed that adding it is difficult if you keep it too far away.
As an example flow I would like to know when my washing machine is ready, so that I do not forget to take the laundry out. Because the washing machine always makes movements / shocks, we could register it with the shock sensor. We will use the vibration value for this. If it exceeds a certain value, I know that the washing machine is on and if it falls below this value, it is ready.
I currently have an intermediate plug on the washing machine to also be able to determine if it is running. So I can nicely compare these values with the shock sensor. After 2 weeks of testing I came to the following conclusions:
The shock sensor never returns a zero value, which means that sometimes it barely returns a value. This can of course have to do with the fact that the washing machine is running but does not give enough results. It will of course only really move when the machine starts centrifuging. Both is the case. This sensor does not display the vibration level in real time. He collects it and then returns the largest value every 300 seconds. This makes it difficult to determine whether the washing machine is switched on.
There is also a vibration alarm that works in real time but it does not turn out enough or precisely when the machine is not running. This is therefore not really useful for my situation.
Back to determining whether the washing machine is on. I have found that he always exceeds 90 vibrations and is then ready within 30 minutes. So I use this value to make my flow. First I check whether the vibration exceeds 90 and the hourglass does not run (to prevent it from starting several times). If this is the case, I convert an hourglass (18000 sec.).
After this I make another flow to check whether the hourglass is empty. If this is the case, I check again if the vibration value is less than 90.
This is to prevent me from receiving multiple messages on my phone. Finally I send a message. If, by the way, the vibration value is higher than 90, I reset the hourglass again this time for 600 sec.
This way seems to work nicely. It sometimes happens that the machine is already ready and I receive a message later but that is not such a problem. If you want to use a more accurate method, an intermediate plug works better.