If you are going to automate lights at home, you can’t ignore the strongest and the most persistent light source: the Sun. Available in abundance at insane light levels, it has the power to light up and warm up the interiors, but also ruin a movie or overheat your bedroom to the point of suffering. When planning light automation, you should really consider automating your windows as well. Previously, I took a look at smart curtains (review) and smart blinds (review), now Zemismart strikes again! This time with a chain-link controller for vertical blinds.
Zemismart chain motor
The idea is pretty simple. A network-attached motor to grab the chain and move it from you from position A to position B. You can automate vertical blinds within minutes. Or hours, if you are me, and the vertical blinds that I own have the controlling chain on the wrong side of the window. Zemismart vertical blinds controller uses mains to power up the motor and the WiFi chip. Therefore it’s best to mount this on the side of the window closest to a socket.
Most of the vertical blinds (mine were very old and overly engineered) will let you pick the drive side. Even if you already ordered it, with a bit of patience and basic tools, you can change the side that the vertical blinds are operated from.
Once that’s done, adding Zemismart chain motor is very simple. Included inside the box is a paper template which you SHOULD use to figure out the position of the bracket. The motor can be adjusted vertically, so don’t make the chain tight. The template should let the chain wrap around without tension. I have to stress this enough, as the first time I have done so – I made the obvious mistake of introducing too much tension to the chain.
Before you can use Zemismart chain motor, you have to set the limits. These will tell the device where is the open and close position. Hold up the middle button for a couple of seconds and drive the curtains to a close position, then stop it with the middle button. Repeat the same for the opposite way. Once you set this – you can use Tuya app to connect to the controller.
Time will tell if these can be flashed with Tuya-convert, but for now, I will focus on stock functions. Once paired, the curtains can be operated with an RF433 remote, Tuya app via phone and smart assistants like Alexa and Google Assistant by adding relevant skills.
The motor isn’t silent, it takes about 2-3 seconds for the verticals to fully open/close, I have an impression that there is a very unhappy screaming banshee inside tasked with winding up all gears. Someone should feed this monster some oil. Thankfully this only last a moment. Since these are fitted to a window next to the TV, I can stop the sunlight from ruining a movie with a single click of a remote or a voice action. I will automate this soon as well (I have done so in my bedroom)
The app itself is sufficient, responsive, but one thing that is missing is the animation for the blinds in question. They show up as curtains. It’s a shame as both curtains and blinds already come with nice visuals. There is an automation panel than you can use to set custom rules like open at sunset etc or link devices in groups. If you have a temperature sensor that works with tuya, like the one in Benexmart Zigbee Kit (review) you can set the threshold to close the vertical blinds to prevent the room from overheating.
The weak points
There are a couple of obvious downsides. The noise was the one I mentioned earlier. The unit is powered by mains. You will need a power socket nearby or figure out how to feed the power to Zemismart chain motor. It may not be ideal for your setup, but I have the battery-operated version on the way, and I will be posting about it soon.
Vertical blinds come with a second loop that slides blinds to one side (or both sides) and Zemismart chain motor has no ability to control it. You can only rotate the angle of the blinds.
Inside Zemismart chain motor
There is surprisingly a lot of space inside. Access is very easy, the top cover pops open easily revealing a 55 RPM motor and an ESP8266EX based TYWE1S module soldered to a PCB. The PCB comes with a motor driver and an RF433 controller which works independently from the microcontroller.
There are dev pads and a header present on the board but it doesn’t link to anything useful. I will definitely hack this thing next as TYWE1S are easy to work with. I will link the guide once it’s ready.
It’s a very cool way of automating light coming into the room. As with automated lights, you don’t truly appreciate the feature and the convenience until it’s deployed and working as intended. Since it’s Tuya based, I will be trying to flash it and integrate it with my home automation server running NodeRED. Amazon has it for about £66 but you can get it a little cheaper on Zemismart page. Let me know what do you think about these in this Reddit thread.