[djwakelee]

For 3 phase, understand the Vue2 is only compatible with Y (Wye) type configuration with neutral.  If your 3 phase is Delta type or without neutral, it wouldn’t work properly.  The majority of people use the Vue2 with residential split phase 240V/120V in the US (and 240V single phase in other countries), in which case it correctly measures real power on all circuits.  3 phase commercial setups are not as popular, but are supposed to be supported if up to 415Y/240VAC Y type with nuetral.  Perhaps some other folks with that setup can chime in and report if they see in discrepancies in operation with 3 phase setups (as well as what country).

You may want to verify your 3 phase hookup, and/or contact Emporia chat.  They don’t seem to monitor this forum as much as they used to.

• This reply was modified 3 years ago by djwakelee.

[djwakelee]

From Emporia chat…

“we measure apparent and real power, and use real power on all circuits”

The poster who theorized VA measurement on the 16 circuits did mention 3 phase – so maybe there is some bug there.  But with 120V/240V split phase in the US, I see accurate W (real power) for the 16 circuits and mains with mixed power factor loads – as confirmed by Emporia.

[djwakelee]

My experience is different.  I have all circuits monitored, and zero balance (or so).  At times there are plenty of inductive loads (AC compressor, pool pumps, forced air blower), which greatly exceed any 1.0 power factor devices.  The math always adds up with the individual circuits, balance, and mains – within that 2% tolerance.  If the circuits were only measuring apparent power (VA), things would be way off.

The original Vue 1 only measured VA (apparent power), and was horribly inaccurate for non-resistive loads.  The Vue2 is spec’d to measure true power, and I have no reason to believe this is only on the mains.  My observations do not support that conclusion at all.

Would like to hear from Emporia regarding this.

[djwakelee]

In the amps view, you are seeing the total amps on each leg, but the circuits are not broken out per leg – just a big list.  So those shown can be on either leg.

Know that the Amps feature is relatively new to the app, and has bugs.  It is also not really what it appears.  The Vue2 only sends real power to the cloud – the Amps values are just divided by an assumed 120V voltage.  Based on actual line voltage and type of load (resistive, capacitive, inductive), the reading may not match the actual amps flowing through the circuit (only if resistive load – and exactly 120V line voltage).  It also shows incorrect 2x current if you use a multiplier for single clamp 240V circuits.

The Vue2 is an excellent and accurate power (W/kW) and energy meter (kWh), but presently missing things like real amps and power factor.  If you can switch to W view, that is how your energy company bills you, and that’s really where the device displays information correctly.

• This reply was modified 3 years, 1 month ago by djwakelee.

[djwakelee]

Known bug.  When you set a multiplier presently (such as single clamp 240V), the Amps reading is also doubled.

Also, know that Amps value is presently manufactured – the Vue2 only sends real power to the cloud.  We don’t get to see real Amps draw – just the power divided by assumed 120V line voltage, which doesn’t take into account real/apparent power and phase angle for AC loads (resistive/capacitive/inductive).  So the Amps shown at present is not necessarily what you’d measure with a DVM clamp meter on that circuit.

Emporia has promised an update handle 240V circuits better (and presumably fix this bug), but unknown when this is due now.

• This reply was modified 3 years, 1 month ago by djwakelee.

[djwakelee]

You can do this with the present notifications.  Add a new custom alert, and pick then ‘Mains’ circuit.  You can specify the kW you want to be notified of (can’t specify amps, but you can convert to kW).  So for your example of 65% for a 200A service, 200A x 240V = 48kW x 0.65 = 31.2kW.  You can spec an interval down to as low as 1 second.

There is also a built-in notification alert for when you hit a peak for the month also.

Also, you typically want to be looking at this in terms of power anyway.  The Vue2 is and energy/power meter (kW and kWh), and not really a good current meter (A).  Know that Emporia presently does not give you a true Amps value, it only records real power to the cloud.  The Amps value shown is manufactured – the true Amps value (with no relationship to power factor) is not shared.  This is a known limitation in their present implementation.  Requests have been made to indicate current (A), Apparent Power (VA), and power factor – but unclear if this will ever be implemented.

 

 

[djwakelee]

I’m far from an expert on UK wiring, but it sounds like your RCD (residual current device) is the same concept as our GFCI’s (ground fault circuit interruptor) here in the US. Since the Emporia wiring doesn’t leave the electrical box, a connection through a special fault protection device like that is not needed – you’d normally just connect it to a standard circuit breaker. However, if the way your electrical box is setup there is an RCD upstream that protects all the other individual circuits in the box, then I understand why you have to would need to deal with this.

Fundamentally, when connecting up through any fault protection device, you have to have all the current go through the same supply and return wiring that the device monitors. If the protection device sees a mismatch between the supply and return current of a certain amount, it trips. It sounds like you had the white wire go back to the RCD monitored neutral circuit, but the blue and red return elsewhere to an un-monitored neutral bar. Since there is current in those other wires (though small), your fancy RCD is not going to like that and think there is an actual fault.

If you can post a photo it would probably help. But if you are installing Emporia on a new single pole circuit (dedicated circuit breaker), that would go to the black lead and all the other wires (white/blue/red) would go to where you connect your neutral return wires in the box. If you are installing a double pole breaker or fault protected breaker like an RCD (which switches 240V hot and potentially neutral), your hot would go to the black wire and all the other 3 wires go to the neutral output of the protection device.

Hope that makes sense. If it makes it easier, for your 240V application, think of the Emporia black wire as the power feed (hot wire), and all the other wires (white/blue/red) as a single neutral. What’s really going on is the blue and red are the other ‘unused’ hot phases – they are not used in single phase applications and must be tied to neutral (white) so there is no induced voltage on them to confuse the system.

• This reply was modified 3 years, 1 month ago by djwakelee.

[djwakelee]

In the setup you describe, you are measuring the combined current for each wire as accurate as possible.  But the voltage being used (for the power calculation) is actually just one of the 120V phases and not the correct 240V total.  Emporia doesn’t natively support 240V measurement – it doesn’t know you have a 240V circuit.  Likely only a small error if the 120V phases are similar in actual voltage, and the resistive load of the dryer heating elements makes phase angle (critical for power measurement) not come into play here.  In doing it this way, I believe if you switch to Amps view it will also show up as double the actual amount.

[djwakelee]

Probably hard to measure precisely as there is enough variation clamp to clamp – Emporia only guarantees 2% (clamps and sensing).  If your 120V phases are the same voltages, yes – you will not see much error.  But nonetheless, there will be some if your phases aren’t balanced – even if small.  This will also depend on what loads you have, with resistive (like a hot water heater element) being less affected than older non-power factor corrected electronics, and inductive or capacitive loads.

[djwakelee]

Yes, you can add the currents of the 120V or 240V circuits on different phases using the above method (route the other phase backwards through the same CT), but this does not yield a totally accurate power result.  To calculate power, Emporia (or any energy monitor) needs the current of the circuit (from the CT) and the voltage (from the 120/240V input).  It also figures out the phase shift between the current and voltage, which is necessary to calculate real power (W) and not apparent power (VA).  When you mix the two phases in the same CT, the voltage source of only one phase is referenced.  If your 120V legs are not split exactly (one high and one low), that will yield an error in the power calculated.

Also, if you do this with 240V circuits, there is additional error since Emporia currently doesn’t deal well with 240V single clamps – we need to use the kludge multiplier.  And when you do that, the software just multiplies the one phase by 2x, instead of adding the voltage of both phases.  But that is a limitation with single clamp 240V for all circuits right now – not just if you try and combine them.

• This reply was modified 3 years, 1 month ago by djwakelee.

[djwakelee]

Yes, what you summarized it all correct.  Just make sure when you connect the 2nd set of 200A CT’s in your main panel to the Y cable, you ensure they are on the same hot phase.  The red/black coloring on the associated wires downstream does not guarantee this – should confirm with a meter.  You should measure zero volts from the garage main conductor to the house main conductor.  If you measure 240V, you are on different phases – and don’t plug those 2 CT’s into the Y-cable.  Hope that makes sense, and if not comfortable with testing given lethal voltages, an electrician can certainly help.

And yes, you need to do this independent of potentially getting a 2nd Vue2 for your garage setup.  Once you have the 2nd 200A CT’s and Y cables, all your math will be correct with the total power draw from the utility.  Any power not monitored by clamps in your main panel plus any power from the garage will show up as a ‘balance’ figure.

• This reply was modified 3 years, 2 months ago by djwakelee.
• This reply was modified 3 years, 2 months ago by djwakelee.

[djwakelee]

That’s interesting – how the disconnect for the other panel is in the main panel – though fed from different conductors in the meter box.

Without going into the meter box and putting your mains clamps there (before the split), you can add a 3.5mm Y cable and connect another set of CTs to that 100A circuit (right above your existing 200A clamps).  Using the Y cable will parallel the CTs and add up your two mains feeds.  You must parallel the same hot phases for this to work.

With the state of the Emporia software right now (doesn’t scale well with lots of circuits or Vue 2’s), you have two options.  You can treat your garage panel as a sub panel, and connect the mains clamps to the incoming feed as well as all your circuits.  Then you can nest the garage panel under the main panel in the software, and everything will total correctly.  Or…

If you are preparing for the eventual unified circuit view (listing of all circuits for both Vue2’s together), you would not use the mains clamps on the 2nd Vue2 and just treat it standalone for now – using only the 50A CTs.  At least that is what Emporia advised me to do.  I have two Vues’2s in my main panel as I have many more than 16 circuits – basically same scenario as you but all in one panel.  Doing it this way, the ‘main’ Vue2 has all the math correct, but there will be a balance and you have to select the ‘secondary’ Vue2 to see those circuits.

We have been promised a software update to have all the circuits combined/sorted in a single list over multiple Vue 2’s, but it seems to be dragging on.  Would be nice for Emporia to give an update on when combining multiple Vue2 circuits into a single list is planned for.

• This reply was modified 3 years, 2 months ago by djwakelee.

[djwakelee]

Also, you may want to check the Solar Supplement guide.  It shows the two ways the solar is typically connected – and monitored with clamps…

https://www.emporiaenergy.com/Gen%202%20Solar%20Supplement.pdf

[djwakelee]

If you don’t have an Emporia Vue 2 circuit clamp on the solar, it will be an unmonitored circuit and behave as you are seeing.  The inverter and Emporia don’t speak to each other, so you need a clamp for the Vue 2 to know what your solar is generating.  From your screen shots, it doesn’t look like you have that?

As mentioned on the other thread, a photo of setup would be helpful since there are a few ways solar can be wired (and monitored).

[djwakelee]

Based on what you describe, you do have an unmonitored circuit – your solar.  This makes perfect sense why seeing a green (generation) balance during the day, and zero balance at night.

There are a few ways your solar could be connected.  If you have it backfeeding a breaker in your panel, you would put a circuit clamp on it and flag the circuit as solar.  When you do this, you balance will also be zero (or thereabouts) – regardless of day/night or generation amount.  You will see the exact solar generation broken out separately, along with mains and net.  Alternately, if you have your solar line-tapped, you will see what you are describing since there is no clamp on the solar itself, so the software is displaying this as an unknown surplus (balance) during the day.

A photo of how you have your clamps and solar would likely allow for a better explanation, since there are several ways you have things installed.

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