RESOLVED: 1/10 Second Power Outage = Sense Offline

It’s been discussed here before and It finally happened today to me. We had a quick power outage at about 9:31 AM. Not even long enough for the alarm clocks to start flashing 12:00, my access points to turn off or the TV to turn off. At about 9:48 AM, the power went out long enough for everything in the house to power cycle. I didn’t even think to check Sense. I got home from dinner at about 8:40 PM and decided to check Sense and it was offline. I ended up having to flip the breaker to get it back online. I was expecting Sense to show data up to 9:48 AM but was surprised to see that the quick 9:31 AM blip was enough to take Sense offline and it had no data from 9:31 AM to 8:48 PM.


Same thing happened to me 2 days ago, but I was home, and caught it much faster

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Thanks for reporting this. We are going to be working on addressing this issue in the near future!

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@KHouse75 & @mc.mbjones,

Would you mind providing a little information about your internet set ups? Specifically, who your internet provider is, your router model #, your cable modem model # (if applicable), and how you have them all connected. This information will be really helpful in tracking down what may be going on. You can private message me this info if you don’t want to share it publicly.

This happened to both myself and my father a few times. Not sure it has anything to do with internet. It seems if sense has a quick interruption in power it just dies. We both had to unplug it and plug it back in to restart the device.

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Likewise with a recent though rare Fios outage. All other IoT and WiFi devices restored their connection without intervention. Only the Sense had to be power-cycled. Why?

Edit: WiFi was on battery backup at the time.

I don’t think this has anything to do with internet. I was showing that sense was not connected to the access point. It would be nice to have some type of interface to connect to on the sense device to look at logs, raw data, etc. I guess it wouldn’t matter in this case since it wasn’t even connected to wifi.

What appears to be happening based on everyone’s reports is if there is a short power outage, Sense loses its internet connection and has issues reconnecting without a powercycling. It doesn’t have to do with your internet per se, more with how Sense goes about reconnecting to it after a power outage.

I submitted a Problem report in March about this exact problem and was rebuffed then by the old standby - it’s your router!
Hope the Sense team identifies just what the HW/SW issue is within the Sense module. I am not convinced the TEAM has a viable technique or emulator for testing the WiFi connections. They may need some help but will they accept any?

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Here’s some anecdotal data - two nights ago, we lost Internet twice overnight (evidenced by our smartthings going offline and sending a notification).

Sense never missed a beat - in the morning, all the data was there from overnight.


And tossing in my 2cents.

I know originally there were issues that if the wifi network was not present at the exact moment the sense was looking for it, that it would give up looking. I thought I remembered seeing some where (not a release note cause why release notes on firware updates…) that they had fixed that particular issue.

My guess as to what is happening in this case (to be corrected by an EE I’m sure) - based on experience with some other IoT like devices with similar network cards- when there is a power blip, not all of the chips in the unit lose power / drain capacitors at the same rate. So whether the wifi chip drops power but the main board doesn’t, or visa versa, not everything starts up clean and ultimately the box is left in an unhappy state and it requires a reboot.

Just another opinion from the peanut gallery.

Thanks for additional info everyone. @NJHaley, that’s a really useful observation as we try to track this down. I’ve let out engineering team know.

One question for the next time someone experiences this problem is: when a power outage happens and Sense needs to power cycled, do you see a light blinking in the monitor (before the power cycling)? This information would be really helpful!

Just to add more anecdotal information - this weekend we had an hour or so of really sketchy WiFi. Everything connected by cord or wireless was dropping intermittently (more off than on) for that time. Sense was able to keep up, although when WiFi was down obviously we couldn’t get any data.

No power issues, that’s something we only rarely see.

I also experience this issue the other day - Thunderstorm in area, brief flickering of the lights (not sure my UPS even beeped…) but noticed later that Sense was offline.

A report or notification of Sense not “checking in” with the cloud services would be really nice as there was a period a month or so ago where Sense had been offline most of the month and I didn’t realize it. I was just wondering why it was taking so long for it to recognize or characterize the devices within my home…

My sense is within the breaker panel with just the antenna poking out the bottom, so I don’t have any visibility to any LEDs on the unit. May have to look into remounting it outside the cabinet.

I can verify it is definitely not a Wi-Fi Access Point or router issue, as I have had those on / off multiple times in doing other testing with work stuff and Sense always seemed to buffer the data and upload it when things came back online.

I had this happen the other night with a line failure in the city caused a series of short power outages (just long enough to restart cable boxes and flicker lights). Sense was not online after that, did a quick breaker switch to off and then back on, still no activity. Did a power off for one minute and then back on and Sense reconnected.

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When this issue happens to me Sense is still connected to my wifi.

My setup consists of the following:

Gigabit fiber, mikrotik routerboard, netgear POE switch, ubiquiti access points. All of these devices have backup power provided by an APC UPS 1500 with an available runtime of 4+ hours.

Several times sense has not been responding due to power outages. When I log into my Ubiquiti Cloud Manager and view the access points and clients connected, I still see the Sense present. I have not looked to see if a light on the Sense is present - will look next time.

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Thanks for the continued reports everyone! This information is crucial for us to be able to track down and resolve the issue.

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I woke up this morning to find the digital clock time flashing… it appears there was a power surge and subsequently my Sense was offline.

I went out to the circuit breaker box, removed the cover, and looked for a flashing light on the Sense Monitor - none found. After resetting the circuit breaker, i didnt find a flashing light. To be honest, i have never seen a flashing light on the monitor nor did i know one existed.

Resetting the circuit breaker corrected the problem until next time… For me, this is a weekly occurrence.

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I’m sorry that happens! Thanks for checking for the flashing light. I’ve relayed that information to our engineering team.

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Yes, that is right.

We had a couple of short power outages in last few days and each time we had to recycle the
breaker, to which the Sense is connected, to get it working again.

I should mention that the network takes about 3-4 minutes to be restored after a power outage.
Does the Sense unit time out and stop trying to look for a network connection after a few minutes?

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