Numbers Not Adding Up

[matt.culik]

I have a Vue G2. Within the app, I’ve noticed recently that sometimes, the total kW being reported by the individual circuit sensors PLUS the balance adds up to MORE than the total usage shown in the app. And since the usage percentages are calculated as individual usage/total usage, they are also off and add up to more than 100%.

Please see the attached screenshot.

If you add up all the kW numbers, you get 3.848, but the app is reporting 2.89 total usage. And the percentages are wrong because they are using 2.89 as the denominator (example: 1.996/2.89 = 69%, when it should actually be 1.996/3.848 = 52%).

Other than the total, the reported usage numbers look right. For example, the pool pump has its own energy monitor and reports exactly the same 334 watts. And I have a standalone energy monitor on the air handler from an older attempt at energy monitoring that reports ~1000 watts.

Interestingly, the difference between 3.848 and 2.89 is .958. And half of .958 is exactly .479, which is the reported balance. So, it seems the app is SUBTRACTING the balance from the individual sensor usage instead of adding it.

It’s also important to note that this doesn’t happen all the time. For example, as I’m typing this, all the numbers are good.

Any thoughts on what might be going on here? Thanks!

 

[djwakelee]

In your list, I see loads that are 120V, and others that are likely 240V.  Yet you only show one entry for the 240V loads – so I’m guessing you are using 2x multipliers for those, and single clamp?  Not all 240V loads are balanced, so that doesn’t always work.  A 240V water heater would be, but a dryer or stove may not be.  So that’s the first thing to check.

Other thing is do you have any solar or other power generation hooked up (battery storage, etc)?  If you do, that will make things weird also, if they aren’t monitored by the Vue 2 with dedicated clamps.

And finally, I had a scenario where a couple of my circuit clamps were being influenced by adjacent wiring power consumption – and yielded higher readings.  This was not because they weren’t clamped properly (which they need to be), but because the ferrite material in the clamps was cracked.

To troubleshoot, when the mismatch is occurring, turn off each of you monitored load’s circuit breakers and see if you get things to add up properly (or at least close – there will always be a small error).  This will point you to what device / clamp / circuit is involved with this.

Also make sure your two mains clamps and fully closed and secure, as well as all the circuit clamps.

A photo of your setup, as well as list of your 240V circuits and multipliers would also help to see if anything unusual immediately jumps out.

 

[djwakelee]

Also, just noticed that your balance figure is green.  This means the system thinks there is surplus unaccounted power coming from somewhere – being generated, not consumed.  So that is why the math is behaving like a subtraction instead of addition.  When the balance is blue, that means it is un-monitored load (consumption).

So still need to work through what is wrong in the setup, but that explains the math.  My first guess would be unbalanced 240V circuits – which would need two clamps and no multipler to be correct.

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