[BLOG] Dos and Don'ts of Z-Wave Power Reporting

Have you noticed automation slowdowns or even Z-Wave devices that aren’t firing at all? It is likely that one or more your devices are demanding too much Z-Wave bandwidth. One of the biggest bandwidth hogs is unnecessary power reporting [...read more]

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I'm currently struggling with this on Hubitat. I set up two ZOOZ Zen15s to monitor a sump pump and a dehumidifier. I am getting way too much info to make sense of it. I had one of the Zen15 at my old house to monitor the sump pump while I was frequently away, using Smartthings V2. That seemed pretty easy to monitor, but I didn't have all of the choices for the device that I have exposed to me in Hubitat. What would be the recommended power characteristics that I should be monitoring, given that I only want to know the device was running and for how long. I don't care about the power consumption, just that the device was running. Also, what should be the frequency of the reporting?

I'm not experiencing any congestion (yet) since I have only installed less than 10 Z-Wave devices, with an additional 20 planned to be installed over the next couple of weeks.

What are you looking to monitor? Their power usage to see when (and if) they're running? If so, you can disable all reports except power reports (Watts). These other reports include energy (kWh), current (volts--and generally uninteresting unless you care about the characteristics of your home's power supply), and electrical current (Amps, also not interesting since it can be calculated from Watts and Volts, though you could use it instead of power/Watts if you want--my brain just thinks more easily in Watts, and the device doesn't provide as much configuration as it does for power, so I see no reason to).

Then, you can make the power settings whatever works for you. You can use either or both the percent-based or actual-Watt-change based parameters (but at least one, of course) to dial reporting up or down to events that give you meaningful information. For my dehumidifier, I'm using a 50 W change and a 50% change, and that works for me to determine off, running, or fan-only mode. I could probably get by with less reporting too, but it doesn't generate enough activity to bother me. You'll have to adjust according to the characteristics of your particular device (so don't just take my numbers as some sort of ideal), and you can look at the "Events" button on the device page to see what things you're getting and how meaningful they are to you.

Alternatively, if you just care to see that it has run, you could disable all reporting except energy. Then, if that value hasn't changed (increased) in a while, you know it hasn't run since it last increased. The unit here, kWh, is probably the same you see on your utility bill, and it tracks how much energy you've used (power times time, cumulative). It won't be great for telling you the current state (so probably not good for my dehumidifier state graph or my "washing machine is done" notification), but if you don't need that, it could be a less chatty alternative.

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Thanks. I think I will start with Watts and see how that goes. I just want to see when and for how long it runs for. It may take a couple of days since the forecast doesn't call for rain. How often do you have the device send a report? Every minute, every five, etc?

The ZEN15 does not provide options for time-based power reporting (at least not in the stock driver, though I doubt the device supports it either then--but if you're seeing time-based options, you are probably looking at the wrong thing). For power, you only have options based on change, whether by percent or absolute value.

I have the ZooZ Zen 15 Ver. 2, and it has working options to report on "Value Change" (i.e., so many watts), "Percentage Change" (i.e., so much percent from last reading), and "interval change" (i.e., every so many minutes). Since you cannot program-ably change these in a rule (i.e., start reporting frequently only when a big change is detected) I have mine reporting once every 2 minutes all the time. I also have the percentage change set to 10%. In this way, when the device I'm monitoring—in my case a washing machine—starts running then the value changes frequently and I get updates every few seconds on average until it is done. This was my compromise. I see no Hubitat degradation, but this is my only z-wave device so far (all others are Zigbee).

Ah, yes, I didn't see the power reporting frequency option on mine for some reason, but the device does indeed support it. So, you really have three ways you can configure that. You can use any combination of the three that get you the data you need. For me, the change-based ones make the most sense (and I really don't like "every X minutes" reporting anyway, though if that's all you do and the device would be pretty chatty with change-based ones and you don't need that kind of resolution, then it may be better in the end). So, I have everything else--including this--disabled.

But again, the characteristics of your device and the needs you have for the data will affect what setting work best for you.