It's common to have PoE switches on the same UPS as the principal server. You can run a NUT upsd on your server to manage the shutdown, so all you really need is a NUT upsmon client for your hub... 
You should probably look in HPM for the app called "Power Outage Monitor" that will allow you to have the hub do various things at different times when the power goes out. It will also do recovery actions as well.
If you get the device like the USB-C UPS or the Konnected one you may need a way to restart the hub after power is restored. You can do this with USB Power smart switches. Sonoff and and Splenssy Tuya Smart USB Switch make some.
So what you need are as follows
- A device that can sense when mains power is lost. Most of the time the devices that do this are Ring Sensors that can be attached to mains wall power and have a battery for backup power. A large computer UPS can also potentially be used for this.
- Power Outage Monitor Smartapp to allow you to manage actions for power down when power is lost and recovery when it is restored and the hub is powered back up.
- A battery backup of which there are a variety out there. You just need to make sure it will provide power uninterupted power when mains is lost
- And the switch device that goes inbetween the hub and the backup power source. This will bee needed to restart cut and restore power to the hub to initiate a clean restart when power is restored if needed.
1 Like
Or you can restart your hub manually as long as you have physical access. There really isn't a need to cut power to the hub... just shut it down gracefully.
When you initiate a shutdown it just puts the hub in a state to have the power pulled. So you need to have some ability to cut power from it completely and then restore it. If you don't have physical access to the hub then the USB switch could be needed.
But ofcourse if you always have physical access then it may not be needed.
Thank you very much for taking the time to provide all that info. Exactly what I was looking for.
Ring extender is perfect for detecting power lost. It has built in battery as well. Unless you are not into Z-wave.
https://www.bestbuy.com/site/ring-alarm-range-extender-2nd-gen-white/6403962.p?intl=nosplash&skuId=6403962
1 Like
Exactly. I know when power is out and have numerous things scripted to happen when it occurs based on length of outage. Also my UPSs are more than capable of running for far longer than needed for the backup generator to be fired up and switched over to.
Also if I need to pull power and reapply to get hubitat restarted after a graceful shutdown I can just tell the POE switch to power cycle the POE port its on.
Incredibly simple and elegant.
1 Like
There is one if you are interested:
3 Likes
Hi how are you doing? I am writing you since I finally got the Sonoff USB smartswitch and the Konnected battery backup that you recommended about a month ago. I decided not to purchase the UPS. The power failures could last about 15 minutes and they happen 1 every 2 months. My main concern is that the database in Hubitat doesn't get corrupted if power goes out. I believe that the Konnected backup could do the job for few hours. My question is could the Sonoff start a timer if WiFi fail (my internet is not on UPS) for more than 2 hours then shut down HE? Could it restart if Sonoff Wifi gets a WiFi connection again? Is this posible?
Thank you for your feedback
Best
I would suggest using the Power outage app that @thebearmay created. It has the ability to trigger actions based on a device reporting a power failure.
I would set it out quite a ways. Maybe even test your Konnected battery backup device to see how long it can keep the hub up. The device i have will keep the hub up for over 12 hours so i just set the Power Outage app to shutdown the hub after 5 hours. If i am without power for 5 hours i have much larger issues so i am not worried about having to manually trigger a restart with the USB power adapter I have.
1 Like
I built my own power loss sensor back in 2021 and it has worked flawlessly since. Very simple you just need two components. No electronics components knowledge needed.
- Power sensor/relay
https://www.amazon.com/gp/product/B017743I7S/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1
- Ecolink door/window contact sensor with external contacts.
I use these contact sensors for a lot of projects. They are tried and tested and 100% compatible with Hubitat
When the power goes off the relay closes simulating a contact closing on the battery powered Ecolink sensor and tell Hubitat that the contact is closed and can trigger any rule including shutdown of the hub. You obviously need some sort of ups on your hubs, which I highly recommend anyway.
I have 6 hubs and I use hub mesh to trigger power off of all the hubs with this one sensor. One note is that if you use this method to trigger remote hubs, your network will need power for some time after the outage otherwise the remote hubs will never get the alert.
If you want to buy a similar kit you can find it here.
1 Like
This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.
