WEM3080T Net-metering mode problem in 3-Phase meter

Hi,


I’m having issue while selecting Net-meter mode. It only shows the Export energy in Phase C.


While I’m Exporting electricity on all three phases. I.e. Phase A, Phase B, and Phase C, due to this issue my calculations are going wrong. I need to display combined export on all 3 Phases.


Also once we select Net metering mode, the overview panel seems to go dead and doesn't load graphs most of the time.


Also, can I integrate my WEM3080T with on-grid solar inverter SUN2000-20KTL-m0 with RS485 communication port?


TIA

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Hi:

This is about how to use the NEM(net energy metering) mode
https://www.iammeter.com/docs/net-energy-meter
You should
1 turn on the NEM switch by calling a local API of the three energy meter
2 select NEM mode in IAMMETER cloud.


After you turn on the NEM mode,there will be a fourth column data displayed (As described in the above URL)
And only the fourth column is the NEM result, the first three columns is only the independent result of each phase.

If you still has question, please give us some snapshot (hide the sn) and point out what is the problem you think .



"Also once we select Net metering mode, the overview panel seems to go dead and doesn't load graphs most of the time"

whether you switch to NEM has nothing to do with the uploading.



"Also, can I integrate my WEM3080T with on-grid solar inverter SUN2000-20KTL-m0 with RS485 communication port?"

Sorry ,do not support such features.



"

Hi @laoliu,


Thanks for the response.

Currently I am using my system in Normal mode. As shown below.



The Overview panel looks like this which seems to be correct.



As you can see above the 4th column is calculating overall phase values and giving me combined output.

Once the net metering mode is on, the 4th column stays at "0" for voltage,current,import,export etc.

The Mobile application shows the value of 3rd column as the total energy consumption import/export. Which is incorrect since my other phases are also import/export KwH, though all three phases shows individual values correctly, but the total sum is wrong.


Also after visiting your net meter link. I understand one thing as mentioned below from the link.

"P1 = 2KW (power of phase A, importing power from grid) P2 = 1KW (power of phase B,importing power from grid) P3 = -3KW (power of phase C, exporting power to grid)"


Does this means your system is designed to set Phase A and Phase B as an import phase and Phase C as an export phase?

As iterated earlier, I am exporting KwH from all three phases (Phase A, Phase B and Phase C). If the above statement is correct that means it will not give me my desired value, please correct me if I am wrong.


Attaching one of the snapshot when Net metering mode was "ON".

 

From above picture you can see that my solar is generating 7632W while its exporting to grid only 2923W (Please ignore the "-" as I know that CT direction needs to be changed). While I checked on my Solar application I was Exporting 7000W at that time. 

Also the value 2923W was only of Phase C. If the system all threed phases export then information will be correctly displayed, as I did calculations manually for individually phases.


Hope my all points are clear!

Kindly support.

Hi:

As you can see above the 4th column is calculating overall phase values and giving me combined output.

Once the net metering mode is on, the 4th column stays at "0" for voltage,current,import,export etc.

Yes, no matter in NEM(net energy metering) mode or normal mode.
There are always four columns displayed in the IAMMETER cloud.
The difference is, in normal mode, the fourth column is just the sum of each phase data but the NEM result in NEM mode.

No matter whether in normal mode or NEM mode, there is no specific meaning of the voltage definition in the fourth column voltage display.
So we use the mean voltage value in normal mode and direct use 0 in NEM mode.


The Mobile application shows the value of 3rd column as the total energy consumption import/export. Which is incorrect since my other phases are also import/export KwH, though all three phases shows individual values correctly, but the total sum is wrong.

Sorry,I do not understand this clearly, please give us more information about this question,.
We do not restrict the usage of each phase, there is no such limitation as your description.
In normal mode ,we use the sum of import/export energy reading of each phase (meter type :grid) as the total import/export energy data, the total import/export energy data will be used to calculated the bar graph(hourly, daily,monthly ,yearly) and many reports.


"P1 = 2KW (power of phase A, importing power from grid) P2 = 1KW (power of phase B,importing power from grid) P3 = -3KW (power of phase C, exporting power to grid)"

Does this means your system is designed to set Phase A and Phase B as an import phase and Phase C as an export phase?

of course not, each phase can be measured both import and export energy simultaneously.


From above picture you can see that my solar is generating 7632W while its exporting to grid only 2923W (Please ignore the "-" as I know that CT direction needs to be changed). While I checked on my Solar application I was Exporting 7000W at that time. 

Also the value 2923W was only of Phase C. If the system all threed phases export then information will be correctly displayed, as I did calculations manually for individually phases.

The NEM mode only exist in 3 phase energy meter and all three phase need to be set with the meter type of "grid". which means the energy meter should be installed in the grid side(not the inverter side)
From the pic, it display the inverter power reading, have you just set the phase C in the "grid" type while the other two phase as "inverter" type.
If so ,there will only phase C has export energy , because the export energy reading is only exist in the meter type of "grid"



please let me know the sketch map of your system,how do you install the meter and the meter type of each phase .Then I will help you to resolve your problem.

Please note , if your system and inverter are both three phase ,
you need to install the 3 phase energy meter in inverter side or grid side and set all three phase meter type with "inverter" or "grid"


This is the wiring diagram of 3 phase system 

https://www.iammeter.com/docs/wiring-diagram#3-three-phase-solar-pv-system



Hi @laoliu,Thanks for the response.Currently I am using my system in Normal mode. As shown below.The Overview panel looks like this which seems to be correct.As you can see above the 4th column is calculating overall phase values and giving me combined output.Once the net metering mode is on, the 4th column stays at "0" for voltage,current,import,export etc.The Mobile application shows the value of 3rd column as the total energy consumption import/export. Which is incorrect since my other phases
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