[djwakelee]

For now, you need to manually add the two phases.  Combining them in the software is one of the most requested features, and is supposedly coming with the next major app update.

[djwakelee]

@msturtz The guiding rule for determining balanced or unbalanced 240V (hence one clamp or two) is if your device has a neutral connection.  If it does have a neutral (white wire), you should use two clamps.  Same as a subpanel.  In my case, my hot tub does have a neutral connection (and ground).  Main pumps and heater 240V, circulating pump and electronics on 120V – so substantial imbalance.  No transformer or equipment pack like you mention, 2 hots, neutral, ground directly wired to the controller.  Can’t say which is more common, but my unit is a MasterSpa, Down East model circa 2006.  National Electrical code requires 50A GFCI on hot tub circuit, with neutral wired through the GFCI as is typical.

[djwakelee]

Also, hot tubs typically require clamps for both legs since most hot tubs are unbalanced loads.  Heater and pumps typically 240V, but the electronics often run on just one of the 120V phases.

[djwakelee]

Correct.  For monitoring 240V circuits, you can either…

1) Use one clamp and specify a multiplier of 2.

(or)

2) Use two clamps (one for each hot leg), and manually add the two readings for the total power.

Also – there is a bug presently with Amps regarding incorrect math and false readings.  Only power works correctly as above.

[djwakelee]

Awesome – great to hear.

[djwakelee]

Correct – the CT sensors for the bus bars do not flip open like the other CTs, hence Emporia’s recommendation to have an electrician do the work when using those.  I’m sure you could use a quality brand high-voltage rated insulated screw driver to remove the main breaker and then access the now disconnected bus bars, but not something to be done without understanding the safety implications, proper re-torque specs, etc.

[djwakelee]

For the panels with the integrated meter (California and other western states), Emporia recommends the flexible sensors…

https://www.emporiaenergy.com/flexible-current-sensors

That said, they also say these should be installed by an electrician as you have to disconnect the mains (or main breaker) to install these.  So, not as DIY as the other stuff.

Although you may physically be able to install the clamps before the meter at the incoming conductors, you’d have to open that section of the panel – and it has the anti-tamper tag.  You’d also have to get the sense wires out of that partition – which looks somewhat sealed.  I’m sure your utility company would not approve of this, even though the clamps would not disrupt their measurement.

In your case, if you don’t want to use the alternate clamps – yes, you could monitor all the circuits in this panel with the 50A clamps and not look at the mains.  The software won’t sum the loads, but it will work and you can monitor and graph the individual circuits.  There is a balance figure that will sum the total if you put clamps on everything, but you can’t graph that.  You do have some big current breakers (100A and 70A), but you can use the 50A clamps if they physically fit over the wires and those circuits stay under 50A in normal operation.

• This reply was modified 3 years, 5 months ago by djwakelee.

[djwakelee]

A couple things to try to diagnose further…

Perhaps you maxed out what the system supports when nested.  With the main panel and everything below, that’s 11 Vue’s 2 total – and maybe they only have something like 10 supported.  Try changing one of your other Vue2’s to standalone, and see if solar works as nested – without fouling up your device list.

It could also be that the system does not like negative power on the nested units.  You could try and remove (unplug) the 200A CTs on that Vue 2.  Make sure to set each of 50A CT circuits for the inverters to solar generation in the app.

Anyway, just a couple things I can think to try – in order to pinpoint what is not working right with your setup and their app / system.

[djwakelee]

Nice setup and description.

Nesting of Vue 2’s was just added to the app recently, and there are a variety of issues.  Additionally, the scenario where you have two Vue 2’s in one panel (due to number of circuits) doesn’t work well currently – not quite supported yet.  The list of devices should really be combined / sorted and not nested – but that isn’t done currently.  Additionally, if you do nest in the software as you have done, the balance is incorrect as it doesn’t take into account the 2nd Vue2’s circuits.  Apparently this is only done correctly if the 200A CTs are being used (as with sub-panels).  In this case with additional Vue 2’s in the same sub panel, the 200A CT’s aren’t being used with your 2nd Vue2’s and it doesn’t sum correctly.  Supposedly new software on the way to address that, and better support for 240V circuits.

Currently solar doesn’t seem to work well unless on the main un-nested Vue 2.  If you don’t need to specifically see each circuit in your solar subpanel, you can probably purchase the 50A large clamps and monitor that from your main panel Vue.  Now, that’s assuming you don’t generate more than 12kW of solar (50A) – not sure how much headroom you have on that 200A circuit.  Alternately, if the solar subpanel is physically close to main panel, you can use 2.5mm extension cables and hook the individual solar inverter circuits to channels on the main Vue 2.  Hopefully they support your scenario in the future of a dedicated Vue 2 for solar.

[djwakelee]

Unfortunately you cannot do what you detailed for the incoming two hot legs – which are two different phases.  By putting both hot phases under the same clamp, you will subtract one from the other.  When the two 120V phases are drawing the same power (say 500W on each), you will see a reading of 0W instead of 1000W.  If the phases draw an unbalanced current, you will see the difference only – not the total.

Your options would be to not use the mains clamps (only monitor the circuits you want and the balance), or get the mains wires separated and the two clamps installed – one on each hot leg phase.

Also, I believe all your clamps are installed backwards.  For the mains, you want the arrow on the clamps pointing to the panel, and all the others you want the arrow pointing away from the panel.

And nice job with the sharpie – Emporia could have done a better job with the channel labeling.

 

• This reply was modified 3 years, 6 months ago by djwakelee.

[djwakelee]

I believe you identified the issue – only power readings are fed to the cloud – similar to the raw .csv data that you can request.  So the amps reading in the app is being ‘manufactured’ and not real, since that data was never sent up.  Internally the device itself knows the mains voltages, current on each clamp, and power factor – as it correctly calculates the power.  But without that raw information going to the cloud, it will only be an approximation for anything except W or Wh.

Their focus to date has really been on the energy aspect, not using the device as a Voltmeter or Ammeter.  Seems like a reasonable request to improve – may want to post in the New Feature Request forum here.

• This reply was modified 3 years, 6 months ago by djwakelee.

[djwakelee]

Yes the Vue2 measures voltage (for both phases).  This corrects a big issue issue with the original Vue, where it indeed did make assumptions of 120V and power factor of 1.0, which gave false readings with inductive or capacitive loads.  Basically the original Vue showed you VA for power, and not Watts (which must take into account power factor).  The Vue2’s power reading is quite accurate, +/-2% spec I believe, and generally within that or better – for all types of loads.

If your concern is that they don’t display the mains voltage with the app, that is true.  The app is a work in progress – they just added support to show Amps for both phases separately on the mains (when in Amps view).

• This reply was modified 3 years, 6 months ago by djwakelee.

[djwakelee]

Well this sounds problematic.  A couple questions..

1) Do you have a Vue2 energy monitor as a part of your system, or are you just using the smart plugs and the Emporia app?

2) Can you elaborate on what you mean by the plugs ‘not recovering?’

a) They don’t remember their prior on/off state when power is restored?

b) They can no longer be controlled by the app?

c) The on/off switch on the unit doesn’t function?

d) They don’t show up in the app?

I have some ideas on what might be going on.  Based on the above, the source of the problem can be better identified and perhaps Emporia can fix it.

[djwakelee]

For data usage, you might check a related post (below) which has the data rates detailed based on some use cases.  Believe your numbers are a tad bit low…

Monthly Data Usage

 

[djwakelee]

Can’t help on the WiFi / cellular gateway front, but regarding the consumption data during loss of internet, the Vue 2 is designed to have a constant internet connection to the Emporia cloud.  From what Emporia states, there is limited internal buffer size in the Vue 2 unit itself.  So after a point of no internet, data will be lost for consumption during the lack of internet.  It tries to compensate for this to a degree when it goes back online, but in practice this does not seem to be very accurate like you mention.  Emporia support may be able to chime in on the strategy employed by the device, but you definitely need a stable internet connection if you want good data with the cloud dependent setup that they have.

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