[jj613]

A couple of thoughts:

1) As you say it’s easy to mix up the phases on a large panel.      Double and triple check that you’ve hooked things up the right way.

2) How are you measuring?   Second?  Minute?  Month?   I have issues with the second and minute data and not sure how well you can compare two circuits that you expect to balance.  I don’t know if that will do what you think it should.   But if you are looking at week or month data it ought to behave as you expect.

3) The 3 Amp balance may be when you have the main sensors backwards in relation to the load sensors?  0.1A may be within error margin .. would need more details.

[jj613]

If the 220V device has no neutral wire going into it you can rely on the sides being balanced and you can use one lead and 2X multiplier.

If it has a neutral you have to imagine it might not be balanced and experiment.   I put two leads on my combo washer/dryer.  I found that the second and minute data showed a reasonable amount of imbalance but the week/month energy consumption was within 2%, about a 1kWh per month difference on almost 40kWh usage.     OTOH I have 16 sensors and 50 circuits so there are many things I’d rather be doing with that second sensor than precisely measuring that 2%.

[jj613]

FYI the only 220V device where I thought I might need two sensors is my combo washer/dryer that has a neutral too, and according to its manual has some 120V circuitry inside, like the timer and the light in the dryer.     So I did the same test as you.  If I look as second/minute data I see differences but the week/month data is very balanced and I’m going to take one sensor off.   35.887 / 35.070.   1kWh/month difference, 2% .. not worth the sensor.

 

 

[jj613]

You can put multiple wires in a sensor if they are on the same phase.   It doesn’t matter if they are on a double pole breaker or even if they are adjacent.

Usually, double pole breakers are not on the same phase, whether they are used as 220V or for a common trip and common neutral as in your case, they do not tend to be on the same phase, although it is possible.

The Vue is not very useful with the Disposal BTW.   It doesn’t capture the high peaks of power draw and doesn’t retain the granular usage (a few seconds at a time) for long enough to be useful.   The long-term energy usage of the Disposal is so negligible it doesn’t appear on most graphs and reports.  If, as is typical, you load the dishwasher, turn it on, then run the disposal for a few seconds it will be invisible in your Vue data.

[jj613]

Why do you want to monitor this?   (I don’t mean that critically, i’m genuinely interested in why.)

It seems like the Vue app and the whole system is focused on long term energy consumption.   The second and minute views are incomplete and importantly they can’t be used to manage total instantaneous power consumption.   I think the Vue system with some small improvements COULD do that quite well but not as it works now.

Since it’s mainly about energy consumption over time, an entire circuit using 20W would contribute a negligible amount.  So before they build smaller CTs I’d like to see them update their software to include functions that would make that useful.  I’d love to see subsecond samples, and I’d love to see second and subsecond data stored for longer.

[jj613]

@playfair how do you monitor the disposal?     The *power* usage is transient and the 1-second data gets forgotten very quickly, at least in the app … they don’t even retain it for a day.      Do they retain in longer in the data downloads?  Or are you automatically downloading it frequently?    The *energy* usage is so miniscule that it does not appear at all on day/week/month views.   What am I missing?  Thank you.

[jj613]

This is very nice.  I think I’ll take a stab at it.

How do you get the input phases independently?   The app doesn’t show that.  Is it in the download data?  I haven’t tried that.

I initially put sensors on all my generator loads but that was a mistake.  Some of them are very uninteresting, especially the gas boiler … it peaks at 100 amps and never uses any noteworthy power or energy.   So I added sensors on the generator feed and will move some off the loads to more interesting circuits.

[jj613]

In response to my own question: I learned that you may not run sensor wires, audio or telephone wire etc from the Vue to far away places outside the electric panel.  The Vue and all its sensors and wires need to be treated as live AC power lines, and as such if you want to put sensors far away you need to run wires in conduit or to use NM/MC etc electrical cable to extend into another proper box.  And then you have the issue of distance.   I don’t know if I’ll end up trying this.

[jj613]

@waterboyz you almost certainly don’t need to sensor both sides of these devices.   You may as well prove it to yourself now that you have done it but you’ll be able to recover 3 of the sensors for something else, just remember to set the remaining ones on the 2-pole circuits as “2x” in the app.

 

[jj613]

Thank you @mjmott.   That’s good to know.  I guess you wrote one answer for each phase?  🙂

Now that I’ve installed it I see that the Main channel only reports total energy consumption so it makes sense that the assignment to A/B/C doesn’t matter.  This also answers a related question, does it matter if the main sensors get unplugged then plugged back in backwards or to different main sockets?  I know now it doesn’t matter.

That also explains why blue needs to be tied to neutral when not used.     It prevents measuring noise or anything else.  I was wondering that… thank you.

 

 

[jj613]

I third this.    Even better, make a less-smart socket that just does monitoring.

[jj613]

I second this.

In addition to making on/off OPTIONAL in the app, turning it off should also disable the hard button on the device.

There is s strong reason for this:   You can use smart sockets for circuits that only have one device on them, so you spare one of the 16 probes for that.   But those circuits tend to be critical devices …. fridge, sump pump, garage overhead door.  You don’t want your very non-critical monitoring function to disable your highly critical device function.

 

Ideally you would sell a “not so smart socket” … that just does monitoring and nothing else.

[jj613]

Good idea but until Emporia supports it in software it won’t work.  My solution for now to the 16-channel limit is this:

1. use Smart Sockets.  A lot of circuits feed just one device (fridge, sump pump, etc).  So I use a smart socket for those devices and don’t need to clamp the respective wires in the panel.
2. combine circuits.  I haven’t done this yet, but a lot of circuits feed very little, like the ceiling lights in one room but nothing else.  I haven’t done this yet but I’m going to combine several such circuits in a junction box outside the breaker panel.  I’ll use a 15A breaker and the total consumption will be much less than 15A.
3. Don’t monitor everything.   Some things behave in the way you would expect them to, so you can rely on the Vue to just combine them in the “excess” or “everything else” bucket .. I forget what that’s called.   I’ll adapt this gradually over the first couple of years so that I monitor the things that are most interesting …. whatever I want to put on smart sockets plus 16 more circuits.

[jj613]

One clamp needs to go around both blue wires, the other around both reds.   The optional flexible clamps are bigger, they might fit.    If they fit, they will work as long as your total usage is less than 200 Amps (or 250 amps or so, the actual limit of the sensors is higher than 200).   But if you are actually consuming 300 or 400 amps through a single panel like this you won’t be able to use the Vue or at least not all of its features.

 

[jj613]

I strongly support this idea.  I appreciate the cloud model of your business, and I think it makes sense.   But there is a strong case to be made for SOME local data collection.     Mine is the following:  We get a lot of trees falling on our lines.   These take out power *and* internet.  The Vue is great for managing power draw on my little generator.  I can see what’s going on, how near I am to generator capacity, what devices are drawing power and when …. it’s great.

But what if I have power, and I have local network and wifi in my house, but I don’t have internet service?

There should be a “local mode” where the vue app can connect DIRECTLY to the Vue, over my home network, without the cloud, and do some basic things.  I don’t need full-blown app functionality!   Just the basics to get me through a storm.   This would be SO SO valuable.   Your little device would take my $800 generator and give it manageability features of a $30,000 generator, just like that.  And it would help me when I need power management the most, when I really really NEED it.

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