[msturtz]

@djwakelee that’s not universally true, in fact its actually fairly uncommon.  Most often, a tub will only get 220V, by way of two legs 180 out of phase, and a ground, but NOT a neutral.  Usually the equipment pack will have a small transformer/power supply on or near the circuit board to power the electronics (control panel, lights, audio, etc), but it’s still balanced since that runs on 220 without a neutral.  All the equipment, including pumps, and of course the heater, will always use 220V regardless if there’s a neutral or not.  The one exception is (or was since they aren’t common anymore) was blowers, which could go either way.  Ozone units can be ordered either way, but 220V is very common.

@Max if your hot tub has a neutral wire (white wire, or white tape hopefully, going to the neutral bus bar in the panel, or look in the hot tub panel where the conduit comes in — are there 3 wires or 4?), you technically should use one sensor on each leg, however even if it is there, the huge majority of the tub’s power usage will be balanced, so one sensor on one of the two hot wires, with a multiplier of 2 in the app, will most likely be very close even if a very small part of the load is unbalanced.

• This reply was modified 3 years, 5 months ago by msturtz. Reason: typo / grammatical correction

[msturtz]

I guess the Emporia folks will need to weigh in if that can or will be changed in software, as I’m not sure what the hardware looks like.  I’m telling you what I’ve read elsewhere.

My system, as I described earlier in this post, I had to move the “main” 200A CT’s out beyond the line-side taps, this way they are seeing the NET usage, both buy and sell.  The downside is they don’t show the usage, only the net of use/produce.  Just like you, I added a smaller CT around just the solar (one of the two legs, but its balanced so correction factor 2 in the app works perfectly) — but my solar is just inverters, no battery, no generator.  That CT measures only production, which is also included in the “net” as I described.  This SHOULD mean the app can calculate usage by subtracting production from Net, but they don’t have that functionality.  In other threads they’ve said it’s coming, but they’re a small team, yada yada.  🙂  But that doesn’t help you in your situation.

You almost need two separate devices, one measuring the various production, and one for your usage.  I’m not sure how that would work out though.

Good luck!

[msturtz]

The 50A CT’s only measure in one direction, not both, so if the indicated location is both “buying” and “selling” power, then the data will be incorrect.  If you’re only “selling”, then I’m pretty sure that will work just fine.

[msturtz]

It would help a bit if you provided some sort of one-line drawing…

The Emporia Vue2’s main CT’s have to measure the net.  If you have a line-side tap, you need those CT’s on the upstream (utility) side of the taps.  If you have an Auto Transfer Switch (ATS) for a home standby generator in front of the main panel, your line-side taps are most likely upstream of the ATS:  Utility -> Meter -> (taps here) -> ATS -> main panel  …  In this case, the ATS basically is your main panel, and your main panel becomes a sub-panel.  The Vue’s main CT’s need to be between the Meter and the Taps.  Then you can add one of the smaller CT’s on the solar side of the taps if you want to monitor your solar separately, along with whatever other loads you want to monitor — you’re exactly right.  If you have a contractor adding all this for you, they should be able to move the CT’s if you aren’t comfortable doing it yourself.  If you prefer, you can do as you suggested — let the Vue just monitor the house, and not measure the solar at all, and let the inverter’s monitoring give you the solar production as well as the Net.  I’d imagine that’s fine too.

I’m confused though…  You mentioned an ATS, and you also mentioned backfeeding a generator, on the main panel.  It is absolutely imperative that you NOT backfeed a generator.  You MUST connect a generator the right way, or somebody will get hurt or killed.  Check this out:  https://www.youtube.com/watch?v=XlLkD1ir2t8  ….  If you have an actual Auto Transfer Switch, then you’re good — utility power drops, which will also knock out the solar, the ATS will start the generator and switch the house over, and reverse all that once utility power is back.  If you have a solar battery (Power Wall) providing backup power, your contractor will do this the right way as well.  If you want both, your solar should be upstream of the ATS, so that the ATS will only see the utility power if/when the solar battery is depleted.  It is critical that you understand this though — Do.Not.Ever.Backfeed.A.Generator.

 

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

[msturtz]

I had the same exact problem, I have line-side taps.  I expected to put the Main CT’s right before the main breaker, so they monitored only usage, and a separate CT on the solar, so it only monitors production, and that the app would let me describe my setup and do the right thing.  The reality is far less flexible, there’s no option for this, it only works one way.  @emporiainfo Can this be changed, so the app can be informed of how the Vue is installed so that the calculations can be correct?

For right now, the “main” 200A CT’s need to measure the net usage, including the solar, in other words they want to see exactly what the utility meter shows.  In my setup, the measurements were completely wrong, until I moved the main CT’s to the far side of the taps, meaning between the taps and the utility meter.  I hadn’t wanted to do that because the panel is full and tight, but I managed to make it work, and the data in the app is correct.

Now the problem, which I think is what your question is actually getting at, judging by the screenshot…  On the main screen, it shows Total Usage, and production, and the net of the two.  But if you go to Graphs (or tap one of the items on Main), you can only graph Solar, or the Net.  You can’t graph just total usage.

@emporiainfo Can you fix this?  The data is clearly available, but it can’t be graphed…

[msturtz]

Following up here.  Chatted with support.  The recommendation was to move the main CT’s to be “upstream” of the taps, so that they measure the Net.  Then I still have one 50A CT measuring just production.  So at this point, it looks exactly like it would with solar backfeed.  Of course, everything looks correct now — in the app, where it says “Main”, that’s the NET, but under that it shows production, and then below that you can see Total Usage.

What’s annoying is the Graph page only shows the Net — with blue for net-use, and green for net-produce.  It doesn’t show them separately.

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