Any reason I couldn't use an HS300 for this?

This may be a dumb question, but I figure it’s always better to ask. The very first thing I did when I bought my house was wire the whole thing with Ethernet. In my laundry room, I have a small, wall mounted server rack that has my patch panel, 24 port switch, a shelf that holds my modem, router, and a PoE inject for my WAP. All 4 of these devices plug into a small rack-mounted UPS. I eventually plan to expand this to include a small NAS.

At first I was thinking of getting a HS110 and just plugging the UPS into it and then in Sense I’d just name it “Network Rack”. But then I started thinking maybe I’d want to get an HS300, so I can get power readings for each individual device. I know each one uses a small amount of power, but it would be cool to see them all separated out. I’d just plug the HS300 into the UPS and plug the devices into it instead of directly into the UPS.

I’m sure there are others with a similar network setup. Which way did you choose?

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I use an HS300 for almost the same purpose. I have all my security and camera system plugged into one. I first used an HS110 and then plugged a power strip into it, that monitored all as a whole. I was able to pickup a HS300 for $55 so have individual monitoring for each component now.
It’s a matter of preference in how detailed you want to see it.

Sense probably cant “see” network switches and whatnot behind a UPS so putting things on an HS300 is good for you in terms of drilldown and agnostic for Sense (it wouldn’t pick up most of those devices anyway).

That said, if you intend smartplugging a significant number of additional devices having HS300s is effectively like having 6 individual smartplugs in terms of the networking and processor load on Sense. The reasonable max (as recommended by Sense) is around 20 but mileage will vary and you could see an impact below that.

I have 2 HS300s on network gear and an AV rack. The AV rack (including OLED TV) data is much more interesting than the network gear but I have found seeing PoE load fluctuations (a UniFi 150W) to be interesting … and these can be compared to the switches own energy stats, which is per-port on the PoE.

Final judgement: Put per-device smartplugs on AV gear (particularly almost-impossible-for-Sense-to-detect OLED TVs) before bothering with network gear.

I am a brand new Sense user and have a similar setup . Half-rack of servers, firewall, etc on an APC UPS. I wondered if the UPS was “filtering” out any learning. I was thinking of doing the exact same thing, so I’ll be watching the replies here.

In my case, I have a 1U rackmounted PDU that I would have to get rid of in favor of the HS300, so I am hoping that I do NOT need to do that.

Have you discovered that Sense has NOT seen each individual device yet through the UPS?? Or are you just assuming that will be the case? I’m not there yet either. 'Probably have to wait longer…

Pretty much all DC transformer devices, and especially low power ones, are not going to be detected … and especially if they aren’t going through power cycling (which could potentially clue Sense in to their presence). That’s BEFORE you put them behind a UPS. The real gotcha for Sense in these cases (UPS or not) is that the gear is essentially always on.

You could plug the PDU into a single HS110 and save some Sense processing cycles and probably get ample data.

Save the HS300 for printers and shredder … much more interesting signatures.

I have 3 HS300s on my various entertainment and networking clusters in the house, mostly on electronics and networking gear that I don’t Sense stands a good chance of ever learning or detecting. The server networking cluster has na HS300 post UPS for me. A few considerations:

  • Lots of devices are boring and a waste of a smart plug - most of my individual pieces of server and or networking gear really don’t show much difference in usage over time, or are totally random.
  • Don’t waste smart plug slots - the top limit is 20.
  • I also use the HS300 to turn power on and off to a few “power piggy” devices that are always on standby (Sonos)
  • You might want to try a “traveller” HS110 on all your devices of interest to see which ones you want on individual smart plugs, vs combining.
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To be honest, I don’t have much of a need for many smart outlets. At least not yet… I know I’ve read posts from frustrated people that say Sense will detect something and then forget it and repeat ad nauseum. I’ve only had mine for about 3 weeks, so maybe that will eventually happen to me, who knows. But, Sense has been doing great detecting things in my home. The only major appliance currently not seen is my dishwasher.

It sees my fridge, chest freezer, washing machine, dryer (well, mostly - it’s still learning. Seems to detect it better every time it’s run), stove, oven, water heater all without issues. It also detects my TV turn on without issue (I’m assuming it’s using the network discovery feature) but only sees it turn off about 50% of the time. It will likely never see my AC or furnace because they are both variable speed systems.

I am considering getting 2 HS300s. One for the network rack. That would be 4 devices, probably 5 in the future. One for the entertainment center in the living room. That would be 4 devices, or 5 if I also connect the TV; receiver, PS4, Nintendo Switch, and an air purifier (and as a plus, I could have the air purifier in the living room turn off when I turn the TV on, but it’d still need to be manually turned back on). I might get an HS110 for the air purifier for the bedroom. That would bring my total number of wifi plugs to 9 or 10, and really, most of them are not needed. It would totally be just for more information for myself.

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Seems like a good plan… But warning - smart plugs can be addictive :wink:

Would putting a single HS110 between a UPS and a PDU do the trick for detecting devices? Since each has its own power signature? Or do you require a different smart plug per individual device? That would certainly be better than put one on everything separate.

Whatever is plugged into the smartplug is treated “as a device” by the smartplug itself. Meaning: the power data it generates, that Sense in turn is sucking in via wifi, will represent all the devices combined. Sense will not then do device detection on that data.

By way of examples:

  1. Let’s say Sense natively detects a toaster but not a radio.

  2. You put BOTH the toaster and the radio on a single HS110 or Wemo Insight using a dumb power strip or split cord/plug.

  3. Sense will potentially continue to natively detect the toaster while also being fed the COMBINED data of toaster + radio from the smartplug (via wifi) … that combined data will not get any Sense detection applied to it. The detection, or more correctly device disaggregation (the AI, machine-learning ML stuff) is only happening on the data stream from the mains clamps in your electric panel. Sense will continue to do that despite the smartplug being there so the toaster’s electrical signature will still (potentially) be detected and disaggregate from the overall electrical signal. Sometimes changing things around could affect the signature though so it’s not guaranteed.

I don’t have any smart plugs yet, but from what I understand, Sense will see the smart plug through your network and then ask you what’s plugged into it. So it’s one device per plug. The HS300 is basically 6 separate plugs.

Two issues here:

  • Most server and networking devices are not likely to be found by Sense since they don’t have physics driven on and off signatures. They tend to have an Always On component with somewhat random activity cycles driven by data flow (networking) or processing (servers). That makes all of them good candidates for smartplugs.
  • Some UPSes, that don’t have a simple transfer switch, and offer some filtering likely distort any on/off signatures that might occcur.

What you do next WRT smartplugs depends on what you want to see today, not future considerations (am I helping or hurting detection). If you want to see individual devices, give each one a Smartplug outlet. If you only care about total usage and the big picture, put the whole rack and UPS on a single one (while staying within the power budget of the Smartplug)


I agree. When the signature for the toaster appears, Sense can’t assume that it was coming via the HS110 just because the HS110 recorded similar power increase. I say Similar because the Sense has about 0.5% accuracy and the HS110 an accuracy much worse. Also, the HS110 is only reporting power levels without a signature so no matching signatures.

That is why I don’t associate my HS110 & HS300 with recognized devices. If I did, the power consumption of those devices would go from the accurate Sense value (as long as Sense accurately recognizes at all times) to the inaccurate HS value. Also, it gives me 2 consumption values to look at to verify Sense recognition. For example, the power consumption of the HS110 (SP-Refrig) connected to my refrig is VERY much higher than Sense. If I look at the device Refrig I see that it shows far fewer on times than the device SP-Refrig. Some of those are the refrig doing a defrost cycle. But defrost cycles don’t last 4 to 6 hours!!!

If Sense ever recognizes the defrost cycle and detects the cooling cycle accurately so that it matches SP-Refrig, then I will move the HS somewhere else.

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I follow your logic up to a point but you seem to be conflating detection and tracking … “ongoing disaggregation”. In so far as Sense samples are shorter than the HS110, it has the potential to account for energy consumption more accurately but there are a couple of reasons why a smartplug, I believe, will pretty much always be more accurate:

  • Sense CTs are capable of a wide range of current detection so are (due to physical limitations) limited in their absolute accuracy. The smaller load on a smartplug implies potentially higher accuracy in current measurement.

  • Sense may be precise in it’s current measurement but the detection accuracy and tracking is inherently a guess so adds again to the overall inaccuracy.

That said, Sense is doing something a smartplug can never do … measuring your entire panel’s load and, by the way, doing something smartplugs don’t: keep track of ALL the data from the smartplug.

There are a couple of ways of defining accuracy in this regard:

  1. Simply knowing when a device is on or off, historically.

  2. Accounting for it’s energy consumption (which isn’t necessarily completely dependent on knowing #1).

There are reasons why #1 is actually more crucial than #2. The goal of course is that you get both with Sense alone. The hybrid of Sense + smartplug will help get to that point sooner but I suspect there will always be reasons to have certain devices on separate smartplugs … if only for redundancy.

The reason i put HS110’s out there is to find and help me tune either the massive energy hogs like my dehumidifiers or shut down those things that are always on and dont need to be, like TVs etc. The single HS110 before my UPS helps to remind me when i leave my servers running, which is all i need.


I got an HS300 for my entertainment center, which is where my networking stuff lives. I went with a single plug for all the network stuff, which is just fine; they all draw constant power, for the most part (there’s a hard drive that holds backups which takes more power when it’s running, that’s it). It includes a fiber terminal, AT&T’s router, plus my Apple Time Capsule.
I also have another combination plug; it holds the network connections for my SolarCity solar panels, Lutron dimmer switches, plus a DVD player that’s rarely used, and an AppleTV which is occasionally used but is so low power (I think ~4W peak) that it’s pointless to waste an outlet on it. The other 4 outlets are for a plasma TV (hard for Sense to detect accurately), an HDMI switch that sometimes needs power cycling (the smart outlet means I can ask google to turn it off and on from the couch, rather than getting up to unplug it), speakers which draw too much idle power (10W; I have them turn off overnight and when we’re not at home), and an NVIDIA Shield TV (we use it more than the Apple TV, and it takes a little more power).

Like others, I use a single HS110 that measures the sum of all my networking and static hardware (backup HD’s, etc) consumption. I actually have it before the UPS that powers all this as well so things like UPS recharge draw after an outage is measurable as well.

Personally, I have no need nor desire to see everything in such a finite level as to know that my router is using (for examples) 25W, my VoIP ATA 25W, my Time Capsule 50W, etc etc etc. I’m happy with the HS110 showing that my average consumption as a sum total for all that gear is 65w most of the time.

I also plugged my 75" Plasma TV into the UPS not only for power filtering, but also to have it’s consumption measured under a device instead of “Other” which it would likely have been lumped as until the end of time due to the virtually impossible to detect signature from plasma TV’s.