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Power Monitoring: Emporia Vue

svetz

Works in theory! Practice? That's something else
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The Emporia Vue is a possible power monitoring solution... currently $109 for 8 ports. A number of members like jasonhc73 have given it a thumbs up (see search for more) but also warns it doesn't distinguish between consumption and production in this post.

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Considering current sensors start around $10/each price seems good (although the accuracy of the current sensors might be questionable).
Reviews indicate accuracy is around 2% with the Gen 2... that's probably not including voltage deviations (e.g., 10 amps at 120V is 1200 watts, but if your voltage is 117, then only 1170 watts). App assumes PF=1.

Questions
  1. Any buyer's remorse or better products?
  2. Has anyone done any packet sniffing to see how tough it would be to integrate with a home-brew program to access the raw data over the WiFi? Any packet captures that could be shared?
 
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I’ve had one ( version 1) for a year. Very cost effective.
Mine does infer direction of power flow on the main circuit. It gets it mostly right but sometimes misses a short transition from export to import when a load comes on during low solar output.
Very handy to decide which loads go on critical loads panel and their peak 1 second load. Interesting to watch the various startup transients. Each motor type is unique.
I haven’t sniffed the packets since I don’t rely on it for real-time control, but it is great for planning and general monitoring
 

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I have been using four of their outlet plugs on my higher use grid outlets around the house and shop I am pleased with the results.
Keeps a running tab on yearly, monthly, daily and hourly consumption. These also function as remote on/off switches if preferred.
Smaller and more compact than a kill o watt devise. Allows me to monitor each outlet from my phone with the app.
They cost about <$28> for four plugs on Amazon.
 
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I’m interested to use these to control on/off schedule on a 7-day schedule - will these fit that bill?

Ideally I’d like to use some device like these to program a master/slave load-smoothing control protocol so that when the master fridge is on, all others are switched off and once the master fridge turns off, the first slave fridge is allowed to turn on (blocking all lower-priority loads), etc...

Does anyone know of any monitoring/control solution out there that would allow this kind of protocol to be implemented?
 
I've been thinking about https://www.iotawatt.com. It's also open source so no need to reverse engineer.

From a quick perusal, seems like the iota watt covers monitoring pretty well, but I didn’t see anything indicating switching/control.

As a minimum, I’d like to program on-off schedule on a 7-day timer. Ideally, I’d like to program more complex Time-Of-Use rules to enable certain loads based on time and load status of other loads...
 
I have been using four of their outlet plugs on my higher use grid outlets around the house and shop I am pleased with the results.
Keeps a running tab on yearly, monthly, daily and hourly consumption. These also function as remote on/off switches if preferred.
Smaller and more compact than a kill o watt devise. Allows me to monitor each outlet from my phone with the app.
They cost about <$28> for four plugs on Amazon.

The only negative reviews I saw talked about the WiFi being flakey and difficult-to-connect. Did you have any issues with WiFi?
 
...I’d like to program on-off schedule on a 7-day timer. Ideally, I’d like to program more complex Time-Of-Use rules to enable certain loads based on time and load status of other loads...
FOR COTS, possible a smart hub? https://www.tomsguide.com/us/best-smart-home-hubs,review-3200.html or the open source Home Assistant?
Otherwise you could probably use an Arduino or android app running on a firestick of some other android device in the house that is never turned off?
 
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Checked GitHub for Emperoria Vue, and there are a few hits. This project pulls data from the Emporia site (guessing Emporia's must phone home, seems to run in the amazon cloud and uses IoT MQTT). Here's a note from Emporia on their forums from 5/20:

You’ve probably seen in these forums that we have APIs on our roadmap in the coming months to help our customers integrate the Vue into their smart home ecosystems. We understand that some people may want to log and analyze their data locally; however, our software, hardware, and business is developed around collection and analytics of energy data in the cloud. Therefore, we currently don’t have any plans to support local logging or data collection.

Personally I want something that runs locally (e.g., power outage and internet down).

The IotaWatt API is documented here. Looks like it supports local monitoring. But it doesn't monitor voltage or frequency? So, those are "assumed" (probably set in software). Update: See #12 below.

Of course Current sense transformers aren't that expensive, a $25 Teensy 3.5 has 27 input analog pins...add on a $7 WiFI module... a circuit for for voltage/frequency... hmmmm...

DIY projects:
 
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... But it doesn't monitor voltage or frequency? ...
Looks like you can query for voltage and frequency here: https://docs.iotawatt.com/en/master/query.html#select-series1-series2
Apologies, by it, I meant I don't believe the hardware records voltage or frequency. The software of course needs voltage to calculate watts, so the value you get is a setting rather than a sensor reading.

The statement was based in that the current sensors don't give voltage or frequency.

But fortunately, it looks like I'm wrong:

ref1:
A wall transformer inserted into an ordinary receptacle converts local voltage to a standard reference voltage and allows IoTaWatt to determines line voltage and frequency.

ref2:
For each measurement, IoTaWatt collects sample pairs of voltage and current for one AC cycle, defined as starting at the voltage zero crossing and ending after two more zero crossings. To compute real power (Watts) is the average of the products of voltage and current of each sample pair. IoTaWatt samples each AC cycle about 640 times at 60Hz.

So, with all of that it can also calculate power factor! Woot! (y)

IoTaWatt size: 27mm x 85mm x 125 mm (1.06" x 3.35" x 4.92" (this ref says 5.88 × 3.4 × 1.2 in) +1.5" clearance for connections,
wallwart: 4.2 × 2.3 × 3.5 in

ref3
The basic unit is 85mm x 125mm with an extra 13mm on each end of the V5 for the wall mount tabs.
3.5mm plugs need about 40mm + 15mm extra if you want to unplug them.
You need 45mm on top for the USB and AC plugs, same on the bottom if you do direct reference three-phase.
So overall width 55 + 85 + 55 = 195mm = 7.7"
overall height = 13 + 125 + 45 = 183mm = 7.2"
 
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The one thing I noticed is IoTaWatt appears to average values over 5 second period.. so if something drew 0 watts for 2 seconds and non-zero for 3 more it would not show it was at 0 watts for part of that time.
 
FOR COTS, possible a smart hub? https://www.tomsguide.com/us/best-smart-home-hubs,review-3200.html or the open source Home Assistant?
Otherwise you could probably use an Arduino or android app running on a firestick of some other android device in the house that is never turned off?

Not sure what COTS is, but sounds like Smarthome technology is the thing to check out.

I know I could make something work of I want to start cobbling but I was hoping to find something one step more advanced than a programmable 7-day timer...
 
I'd suggest the Hubitat Elevation. https://hubitat.com/ Basically the only Smart Hub that keeps running completely independent of the internet.
Very fine grained control of things. You can reach it over the net, but it will keep turning things on/off, running the thermostat, monitoring motion, and everything completely without the network. While they have just introduced some network access options, I've had one for years and their network options aren't really necessary.
 
I'd suggest the Hubitat Elevation. https://hubitat.com/ Basically the only Smart Hub that keeps running completely independent of the internet.
Very fine grained control of things. You can reach it over the net, but it will keep turning things on/off, running the thermostat, monitoring motion, and everything completely without the network. While they have just introduced some network access options, I've had one for years and their network options aren't really necessary.

Cool, I will check it out.

Any way to program it so that one load running can be detected to turn off / block another load? (Or load turning off an be used to turn on another load?).
 
Cool, I will check it out.

Any way to program it so that one load running can be detected to turn off / block another load? (Or load turning off an be used to turn on another load?).
Most of the zwave devices that one uses to control devices report watts regularly. So for most household level devices, sure. If the loads you want to control are more than ~1500W, then you'd have to use an intermediate relay.
see https://www.getzooz.com/portfolio-zooz.html for a representative sample of device capabilities. There are lots of suppliers.
 
Most of the zwave devices that one uses to control devices report watts regularly. So for most household level devices, sure. If the loads you want to control are more than ~1500W, then you'd have to use an intermediate relay.
see https://www.getzooz.com/portfolio-zooz.html for a representative sample of device capabilities. There are lots of suppliers.

The highest-power devices I’m trying to control are under 1kW, so sounds like no external relays would be needed.

Just to make sure the capability I’m hoping for is there, let me sketch a real-world example:

Both primary refrigerator and chest freezer connected to independent monitors/switches.

Program controller so that whenever primary fridge is on a drawing more-than-standby current, chest freezer switch turn off so that if chest freezer was running, it stops, and if it was already off, it is prevented from turning on until primary fridge is off again.

Is that kind of control possible / easy?

Ideally I’d like the control to extend to a 3rd slave device which is only enabled when both primary fridge and chest freezer are off / standby and not drawing substantive current, and I’d like some time-based rules to only apply this master-slave control during certain hours of the day (or when mains power drops below a threshold), it just being able to master/slave two devices would be a great start...
 
The highest-power devices I’m trying to control are under 1kW, so sounds like no external relays would be needed.

Just to make sure the capability I’m hoping for is there, let me sketch a real-world example:

Both primary refrigerator and chest freezer connected to independent monitors/switches.

Program controller so that whenever primary fridge is on a drawing more-than-standby current, chest freezer switch turn off so that if chest freezer was running, it stops, and if it was already off, it is prevented from turning on until primary fridge is off again.

Is that kind of control possible / easy?

Ideally I’d like the control to extend to a 3rd slave device which is only enabled when both primary fridge and chest freezer are off / standby and not drawing substantive current, and I’d like some time-based rules to only apply this master-slave control during certain hours of the day (or when mains power drops below a threshold), it just being able to master/slave two devices would be a great start...
All of the above is quite possible. The hub can be notified on a change in power level for each device, that change can trigger one or more rules.
The rules can be arbitrarily complex, conditioned on time, relative delays, power level of a different device, previous state changes, etc.
However... designing the rules to achieve said complexity does require thinking quite carefully about the logic. I have found that it is often simpler to have some intermediate, global, logical variables that encapsulate particular states. The device control rules work from them and it is easier to trace and debug.

The devices can either report on a time interval or power change. Make sure you select power change in the device setup.

It is important to understand that these rules might take a few seconds to execute. Don't count on sub-second control.
 
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I'd suggest the Hubitat Elevation. https://hubitat.com/ Basically the only Smart Hub that keeps running completely independent of the internet.
No WiFi? Needs a physical ethernet cable?

...network options aren't really necessary...
What are they used for anyway? With SmartThings I send text messages to my cell phone to get alerts of things I need to take action on... what do you do to avoid the internet for those types of things?
 
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