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Strange Measurements on consumption / return


Luxirom

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I seem to have a strange behaviour on my shelly 3 pro PM:

in short: the more solar energy i produce, the higher my own consumption seems to be.
so far i did not optimize any of the consumers to actually turn on when more solar is available.

my calc in home assistant shows this (but it is also visible in shelly dashboard):
i calculate "total solar produced" + shelly total active power.

or in the name of sensors: (Solaredge (AC Power) + "Shellypro total active power".

 

In my understanding - if my own consumption over the day stays the same - this should indicate more return with stable consumption?
in my calcluation however, the higher the production, the higher the consumption.

am i using the wrong numbers? it doesnt matter if i use power or energy (in kwh). the pattern stays the same.

https://ibb.co/4f94hbh

 

could this be because of wrong wiring of the 3 phases?

 

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Unfortunately, I don't quite understand your problem yet.

It would be helpful if you could explain the colors shown in the graph. 
Where is the Shelly Pro 3EM located? Directly behind the electricity meter?
Are you only measuring with one Shelly or 2?

If the phases are wired incorrectly, there are indeed strange measured values, but the problem usually lies elsewhere.

Have you heard about the balancing issue? This could also be a reason why the values appear incorrect to you.

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Hi TVB,

 

thank you for the fast response!

of course explaining the colors would help... my bad 😉

purple: returned energy
blue: imported energy from grid
yellow: consumed self-produced energy.

it is 1 shelly 3 EM pro and it is installed directly on the main line coming into the house from the street (before anything else).

 

I am not aware of balancing issues. Do you have more information about that?

 

Some additional oddity i found is in below screenshot from shelly directly:

i seem to have strange Power-Factors (or at least the one from Phase1) and not nicely balanced phases for return.
phase 1 seems off and also weak in terms of return-energy to the grid.

https://ibb.co/Y3wWNpX

 

I expect that this all is connected and that this is also the reason i get increasing power-use reported with increasing production.

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Ouch,

thats a lot to digest but definitely helps. Many thanks!

I have to discuss this with my electrician as well it seems.

Can't say if thats the cause of my weird Powerfactor but there is enough to go wrong.

I will follow up with findings.

 

Best!

M

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The power factor depends on various characteristics of the connected devices and it is quite different depending on the device/device mix (inductive, capacitive load) what is determined as apparent load.

In electrical alternating current technology, the power factor is the ratio of the amount of active power P to the apparent power S.  

I don't think your power factors are wrong. Have a look at one of my Pro 3EMs here with really very different PFs:

image.thumb.png.ebd15aac600d1a2c9eb1494aef777617.png

Edited by tvbshelly
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Here you can see the 3EM, which is installed directly behind the grid meter: The import/export is very uneven on the individual phases. However, this is not critical because the grid meter balances these values, i.e. if you export exactly 300 W on two phases and import exactly 600 W on the third, the meter counts 0 as consumption:

image.thumb.png.fec6c0737ab730b44b6d8ecf5fe85305.png

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