I have 13 different Shellies, which have been difficult to integrate when I was a “newbie”.
For everyone who has problems with the WIFi connection, try ColoT with your host ip and port 5683, it works for me (edit firewall settings as well):
Btw: The Door Window 2 sensors are “battery sensitive”, the others work without problems for me.
I was shocked to find it doesn’t have a humidity sensor,
DHT22 takes 2 seconds to read and consumes 2.5mA while being read, probably not a great thing to do regularly when you are trying to be ultra low power.
I have two [version 1] they have worked flawlessly for 2 years now. I don’t connect them to the cloud, they are local only.
Thanks but I run all my DHT22’s off the mains so not worried about that at all.
AKA: RTFM. 
Unfortunately, my Shelly Motion devices do not have this option (all my other Shelly devices have it).
It’s probably a firmware issue, I’m running on 20210218-134233/v1.0.3 and have not been able to update yet. They don’t have Internet access, so I can’t do it with the OTA-URL. I do the updates with the 3rd party app Shelly Home, which works great for all my devices except Shelly Motion (where just nothing happens after clicking on Update Devices). 
I might try using MQTT instead, because that option is available in the Web UI.
Current is 20220811-152232/v2.1.8@5afc928c
Why not connect it to the internet to update it?
Because reasons.
But I found a way that works for my level of paranoia:
I hope they work better now with CoIoT enabled. I did not manage to get MQTT to work (at least not with the old firmware).
I bought a Shelly Motion 2 in spite of having read this thread. Fortunately, it’s still within the return window, and it’s taking a trip back to Amazon today. It drops off the network every few hours to days, and the only way to restore it is to factory reset it–which is, in itself, very difficult because with almost every configuration change that requires a reboot, it drops off the network and I have to start over. Like others with trouble, I have Unifi APs. However, the SSID to which the Shelly connects has a vanilla configuration, and my more than 70 other IoT devices remain connected to it without difficulty, though none of them is battery powered.
I opened a ticket with Shelly, and got back an automated email saying they respond to most requests within 72 hours. Compare that to Amazon, which will deliver a new motion sensor to me within about 6 hours. I was really hoping that this Wifi solution would work out, but it’s back to Z-wave for now.
When you say that it “drops off the network” have you tried pinging it from a Linux terminal?
I have quite a few Shelly switches which, after a while, cannot be browsed to but they still work on HA if they are set up correctly.
I can “wake them up” by pinging them with Linux CLI (windows only does 3 pings unless you use the -t option)
It usually takes more than 3 pings to “wake up”.
Thanks, but yes, I have tried pinging. When the device drops off, it doesn’t respond to a ping (forever) and HA shows the entities as unavailable. Pinging a device can’t wake it up anyway unless a programmer has gone to the trouble of intercepting the icmp packet and doing something with it, and that would likely cost more energy than it would save and wouldn’t make sense in this context. Perhaps your device is waking up at regular intervals anyway, and happens to wake up while you’re sending icmp packets. I have tracked my device for several hours after it drops off, and it never returns. Interestingly, when it detects motion in that state, it flashes green instead of red, indicating that it knows it hasn’t sent a packet.
I have also discovered today that resetting with the button isn’t the same as a factory reset. After a button reset it remembers its SSID, but not the password, and several other fields, but not all of them. I was able to get it back on the network (at least temporarily) by resetting with the button, connecting via its own SSID, then doing a factory reset via the web as the first action. After that, I was able to reconfigure it without multiple spontaneous reboots. It has stayed online continuously for 10 hours now which isn’t a record, but is pretty good.
I have 2 other Shelly switches controlling garage doors, but those are grid powered, and they work beautifully.
This thread is primarily about the motion 1. If configured properly, it works fine.
Did you have the series 2 configured with the websocket configured?
I seem to recall that early on this type of problem disappeared after firmware upgrades.
Have you done that Tom?
Also, please confirm the following:-
IP address is reserved in your router
Firmware is up to date
CoIoT is enabled and remote address is HASS_IP_address:5683
Well I have shelly motion 1gen purchased in May 2022 and the battery lasted nearly 1 full year in a busy corridor at home. I suspect if it was in a quieter place it could last 1+ year. So that statement is not untrue.
It is not always connected. It goes to sleep to save power. Thus: untrue.
It is always connected in a sense that if motion is detected it does it’s job. But if you want to be picky then fine - whatever makes you happy.
Point is I have the device and for the past 12+ months I had no issues with it.
Like alfwro13, my experience confirms this marketing claim: I have one that’s run without any charging for about 13 months before I needed to plug it in for a few hours to recharge. The one downside is that after leaving it alone for that long I forgot how the mount works and managed to pull it out of my wall… but I don’t blame Shelly for that!
Based on the delay between trying to connect over wifi I would guess that it sleeps most of the time, but has a quick-wake connected to the motion sensor. It’s probably one of those pyroelectric sensors that are very low-power that trigger the wakeup of the microcontroller. If I try to connect over wifi it just sits for a while, but as soon as I trigger the motion sensor the connection picks right back up, with no wifi disconnect over that time.
The claim is that it is always connected.
You can’t have it both ways. Which is it?
Always connected or not?
I’ve had that exact same Issue.
First few months everything worked perfect, then all of a sudden some S-Motions worked, some didn’t.
Disabled 5Ghz in the IoT WIFI and everything works like a charm now.
This shouldn’t happen tho and you guys know, that this is a firmware bug, that needs to be addressed!
Tell it to Shelly. It’s their firmware.
It is not the right solution to turn off the more modern WIFI 5GHz. Your WIFI network should properly be fully transparent between 2.4GHz and 5GHz transmissions. Then it can’t be a problem…
If you put a username and password on the device for local web browser access to the unit’s hardware, the username should always be “admin” - I ran into the same problem as you - unless I left the detault userid as “admin” - since the shelly integration only ever asks for a password, not any user id (so I assume they have "admin’ hard coded as the user id). Also when you add the device to the shelly phone app (first setting it up), always have the phone on the same vlan to which you are planning to add the shelly device.
