Can I use the 200A clamps for sub connection instead of on main?

[anthonydcc]

I have a main panel with a 100 A line going to a sub panel to my garage workshop. Would I be able to put the Vue in my main panel, use the 16 CT connectors for the rooms in my home, and instead of putting the 200A clamps on the main, put it on the line going to the garage sub panel so that I can view the house usage (combining the 16 CT’s) and the garage usage with one Vue. Or would I need to get two Vue’s?

Thanks!

[djwakelee]

Interesting idea and use of clamps, but the software people didn’t plan for this hookup method.  If you did what you describe, none of the math in the app would sum up correctly.  The software is designed such that …

1) The mains clamps are expected measure the total consumption.

2) The circuit clamps show the power on each monitored circuit (a portion of the total power).

3) A balance figure is calculated that details any difference (to account for un-monitored circuits).

Hooked up as you describe, under light load in your garage the software would think you have an unmonitored power source (say solar generation) since the mains value (really your garage) would be less than all your 16 circuits.  Your total consumption for the property would show be much lower than actual, and would show up as a green balance figure (indicating false on site power production).  Conversely, if your garage was drawing a lot of power (say charging an EV), it won’t think there is extra power from somewhere, but again the total consumption figure will be way low – and only indicate your garage power draw – ignoring the 16 circuit draws in the math.

If you don’t care about looking at or plotting the ‘total power’, your mains clamps on your garage circuit will always show that consumption correctly.  Understand it would be improperly listed as your mains consumption for your property – not a sub item for ‘Garage’.  Your 16 circuit clamps would show the correct power.  Just all the totals would be wrong (and balance figure), and what is referred to as Mains power would be your garage circuit.

The correct thing to do in your case is to have a 2nd Vue 2 for the garage subpanel, and any circuit clamps you wanted to monitor those.  The software will allow you to nest the subpanel Vue 2 underneath the main panel Vue 2, and all the math then works correctly.  That’s the only multiple Vue 2 scenario that works correctly – those of us with more than 16 circuits in a single panel have been waiting for a solution since the product launch.

[anthonydcc]

Ah, I see thank you for your explanation on the software.

 

Then alternatively, as I mainly want to monitor total usage of the home and garage separately, if I simply got two Vue’s without the CT’s to save costs, a Vue for the main panel and the other for the sub panel, does the software have some option to subtract the usage of the garage line from the main? Or would I still need to get the 16 CT’s to sum the lines of the house separately?

[djwakelee]

Yes.  You could get two Vue 2’s without the circuit clamps.  You then tell the software that the garage Vue 2 is nested under the house Vue 2.  Then everything works and you’ll have a total figure, the garage figure, and a balance figure for everything else.  The balance number will be your house-only usage.

[Bob Weinberg]

I wish I had looked for your postings before I tore my hair out ! You have a great handle on this system.  I have engineering background and safely work with AC panels frequently like mine.

Emporia support is helpful but it seems I never get all the info needed when I try something. I’ve had a VUE1 for years and and its worked pretty well. I now have a VUE2 installed in my main panel instead; but I like some others have a subpanel situation. When we built the house we planned for an EV and for solar so we put that subpanel in the garage, and it has several 120V outlets and the garage door opener too (data from which is not needed nor do I care of it messses up net numbers).

The config I started with had 2 CT on L1,L2; at the main panel(lets call them G1 and G2) Those were on the run to the garage off a dedicated 80A breaker.  The way the app and instructions are as you know not enough to tell the whole story of what was going on and I now understand regardless of K-L on this feed where I can have both generation, EV charge, little loads alone or combined at any particular time —– the gross and net numbers in the app will not be correct, and I have placed the 2nd VUE under the main panel. (adding absolute values and negative signs in multiplier do not help.  When the app asked at install whether the panel will have solar (and again when installing a 2nd VUE) I’m not sure what to indicate especially if I would choose solar when I identify the circuit type for G1 and G2 as wired.

I know the idea is to use the solar behind the meter as much as possble because here in Ohio we get credited very little in $; but over the month it does credit KWH correctly as credit not $$. I have a 5KW unit, mid-day more like 3-4kw actual.  My Tesla wall charger can provide 48A AC but I rarely tell the vehicle to use more than say 10A as I usually can wait long enough; and also when to begin charge time.

Ive tried to move my VUE1 into the subpanel, but not seeing what I thought I would and realize the 2nd VUE2 is the right thing to use and so I have another I would substitute.

Big questions:  Given the panel arrangements and subpanel how do I setup and answer the questions from the app so I wind up with the best way to see loads normally that have a CT;  Main CTs placed as usual or differently at the subpanel.  And to see at least the solar gross output somehow through the VUE system.  (My SolarEdge inverter has a revenue grade meter within it and reports to their cloud properly but I would like to just refer to the VUE app to show it all.   Same for the EV charging.  With the net appearing in some useful manner in the app.  And thereby the ability to set up some notifications as well.

Thank you so much for your patience and i hope you can give me the needed tips for my topology.

 

Bob

 

 

 

 

 

• This reply was modified 1 year, 11 months ago by Bob Weinberg.

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