Domoticz

I'd like to suggest a few enhancements to the p1meter plugin.

Background for my request, imagine the following extreme situation:
L1 has a one phase solar panel convertor connected, this is where all the return happens
The house has all the power usage on L2 and L3
-> Nothing of the solar energy is used in the house, everything goes to grid (L1) where in parallel power is still consumed on L2 and L3...

What I'd like to see:
1. For the main P1 electricity device (widget), total usage for today is shown.
Would it be possible to implement this as well for Usage_L1,L2 andL3?
It would be interesting to know whether the load in a house is evenly distributed over the three phases....
2. Show the total return for L1, L2 and L3 for today on the widget.
Is the solar panel return evenly distributed?
3. Would it be possible to have another device for L1, L2 and L3 that calculates todays result of nett solar+usage (L return- L usage)?
4. Log graphs: Show L1,L2 and L3 in the same graph (like the main electricity device does for usage1+usage2, the timeslots)

I can't create something like above myself, but happy to assist in a branstorming session

Hi, @diekli ,

I want to react on your suggestions for "enhancements" for the P1 Smart Meter hardware.

This is not a external plugin, but is available in the Domoticz hardware by default.

You made a sketch of an extreme situation:

L1 has a one phase solar panel convertor connected, this is where all the return happens
The house has all the power usage on L2 and L3
-> Nothing of the solar energy is used in the house, everything goes to grid (L1) where in parallel power is still consumed on L2 and L3.

In relation to solar panels, you have different possibilities:

1. Single phase solar (string) inverter. This inverter is connected to one of the 3 phases (L1, L2 or L3). As a result the produced electricity is used by all equipment, which is connected to that phase. The over produced electricity is fed to the grid on that particular phase.
Indeed it might happen that a specific phase is not consuming any electricity at a specific moment. In that case all produced electricity is fed to the grid.

2. Three phase solar (string) inverter. This inverter is connected to all 3 phases. (L1, L2 and L3. As a result the produced electricity is used by all equipment, which is connected to all phases. The over produced electricity is fed to the grid on all phases.

3. Micro inverters. You can connect these to one, two and all the 3 phases. What ever you like. They will use the produced energy dependent on the load of the phase. This situation is equal to 3 times situation 1.

For the main P1 electricity device (widget), total usage for today is shown.

Correct. This is a positive value in case of usage and a negative value in case of return

I do not understand what you mean with "for today". Is that energy? Expressed in kWh?

Would it be possible to implement this as well for Usage_L1,L2 andL3?

This is already implemented and available (in case of a 3-phase Smartmeter). However if you mean energy in stead of usage, you should know that this data is not delivered in the P1 Smart meter telegram. So if you need it, you can calculate that yourself. E,g use dzVents or Node Red. or something else.
I do not see the practical use of that value. Can you explain your intended use?

It would be interesting to know whether the load in a house is evenly distributed over the three phases.

Why? I can tell you, it is not. It is the equipment that uses the electricity and that is not constant the same.
You should take care that you do not connect e.g. washing machine, dishwasher, microwave oven, etc to the same electricity circuit and to the same phase and then use it all at the same time!

2. Show the total return for L1, L2 and L3 for today on the widget.

You probably mean the energy , but you started your post with:

L1 has a one phase solar panel convertor connected, this is where all the return happens

So L2 and L3 return is zero!

Is the solar panel return evenly distributed?

Not in your case, as you use a single phase inverter.

Would it be possible to have another device for L1, L2 and L3 that calculates todays result of nett solar+usage (L return- L usage)?

You have to create that yourself and I think your are mixing power usage (W), power return (W) and energy (kWh) with each other.

4. Log graphs: Show L1,L2 and L3 in the same graph

If you want the power usage of L1, L2 and L3 you can try to send these it InfluxdB and show them with Grafana.
Domoticz has a connector for it, available by default.

like the main electricity device does for usage1+usage2, the timeslots

This should not be mixed with T1 and T2, which represent different tariffs.

So I do not see any advantage with the "enhancements". Sorry for that.

Regards

If the P1 plugin would have a connection with a variable that holds the production by the solar inverter, the plugin could also display your actual consumption (being the sum that is produced by the solar + usage from grid - delivery to grid)

Hi.

If the P1 plugin would have a connection with a variable that holds the production by the solar inverter

Why should this be needed? We have many different brands of inverters. For most of them, we have a plugin or script, that indicates the produced power of the inverter(s). So this value is available and you can program, whatever you want.

For an idea, you can look at: https://www.home-assistant.io/blog/2021 ... anagement/ or https://www.home-assistant.io/home-energy-management/

Regards

There are some recent changes in Domoticz beta to add L devices for usage and return.

Thank you all for responding, let me try to clarify.

In the 2022.1 version I have the three phases for both usages and return, right?
So in a script I can do the calculation of the nett result:
nett_energy_usage_result = (0 - ( p1usagel1+ p1usagel2+ p1usagel3)) + p1deliveryl1 + p1deliveryl2 + p1deliveryl3
This provides the TOTAL actual value at that point in time (in kW).
However you may paying for electricity on L2 and L3, where - at the same time - L1 has a return (you are receiving money).

So I'd like to see per Line how does it look per day? Is the energy returned and used (per line) evenly distributed?
Or do I have an unbalanced situation where once the netting (Dutch: saldering) is gone, I may be shocked that I am going to pay so much more, since I am not using any energy produced by the Solar Panel.

Ps. I do have an 'Electricity' background. My example was to paint a picture that people can relate to. I do have a 3phase solar panel convertor
I think 99% of people don't realise what the impact will be to have a 1phase convertor on a Line which does not have a (lot of) load (=devices) on it.
And at this point in time I can not see this info myself (and I don't want to learn or build a Grafana setup)

Hello all,

@waltervl

There are some recent changes in Domoticz beta to add L devices for usage and return.

Indeed saw that since version 14343 we have a new sensor for the current of the P1 meter.
There has been discussion a long time ago, whether this current sensor would be useful or not .
In the Dutch version of the DSMR 5.1 protocol, the protocol will not supply any digits after the decimal point. So the accuracy of the current is rather low. In the Belgian version the meter will supply 2 digits after the decimal point. For that reason it has, up to now, not been implemented.

In version 14345 there is a Current L1/L2/L3 sensor for delivered.


@diekli

In the 2022.1 version I have the three phases for both usages and return, right?

Since a longer time, in case of a 3-phase smart meter we have available 3 sensors for Power Consumption and also 3 sensors for Power Delivery.
One for each phase. So that is correct.

So in a script I can do the calculation of the nett result:
nett_energy_usage_result = (0 - ( p1usagel1+ p1usagel2+ p1usagel3)) + p1deliveryl1 + p1deliveryl2 + p1deliveryl3
This provides the TOTAL actual value at that point in time (in kW).

That is correct, but is already done by Domoticz in the P1 Smart Meter sensor. A positive value, if you consume power from the grid and a negative value, if you deliver power to the grid. So no need to calculate it again.

However you may paying for electricity on L2 and L3, where - at the same time - L1 has a return (you are receiving money).

I understand your concern, but there is nothing to worry about, as the smart meter makes its own calculation and your are not paying for the power you use for L2 and L3 and receive money back for L1.

Example:

Imagine that you deliver 3kW to the grid on L1 and you consume 1kW from L2 and also 1kW from L3
This does not mean that you pay your price for L2 and L3 consumption and get paid (in the future less than you pay for consumption) for L1.
It means that the smart meter calculates internally that you deliver 1kW to the grid (3-1-1) and you get paid for that.

This is not very well documented on the Internet and very difficult to find.
I found something in Dutch at: https://www.coolblue.nl/zonnepanelen/ad ... imme-meter

This 100% return compensation exists only in the Netherlands at the moment. There are even countries, that don't pay anything for returned power.

So I'd like to see per Line how does it look per day? Is the energy returned and used (per line) evenly distributed?
Or do I have an unbalanced situation where once the netting (Dutch: saldering) is gone, I may be shocked that I am going to pay so much more, since I am not using any energy produced by the Solar Panel.

You always will, as long as the sun shines

I think 99% of people don't realise what the impact will be to have a 1phase convertor on a Line which does not have a (lot of) load (=devices) on it.

Nothing, as you could have read.

FYI I have a electro-technical background as well.

Regards

Hello,

Just my 2 cents...

Its not a good practice to use the 3 fases like you do, if everybody does this the net transformer will get issues, and the voltage could surge over 10% normal voltage resulting in broken applances.(realy; we had this happen in our Residential area)

Just use all 3 phases in balance so fase1 little more than the others, as stated you will get your return in the Netherlands..

The only thing you have to think about is the wiring in the fuse box.
In the Netherlands normally you have 25 ampere breaker giving 5750 watt so if your inverter is puting out 3000 watt the wires have to withstand
8750 watt max.
Electrical scripts are al over the place, just copy, modify and use.. its fun.

For the enhancements, here are mine, P1 port plus solardata: Very satisfying to watch updates every 10 seconds, sometimes things calculate wrong but that is fine with me..

RonkA wrote: ↑Saturday 18 June 2022 14:59
The only thing you have to think about is the wiring in the fuse box.
In the Netherlands normally you have 25 ampere breaker giving 5750 watt so if your inverter is puting out 3000 watt the wires have to withstand
8750 watt max.

What? Normally you don't have a 25A breaker device. An RCD of 40A and then 16A breakers. And if your solar system is correctly installed it is connected to its own RCBO (aardlekautomaat). The value of this RCBO depends on the power your inverter can produce.

I do like your overview from the P1 meter! Did you use any scripts or are these common available objects from the P1 meter?

Hi,
To clarify;

What? Normally you don't have a 25A breaker device

Normally you dont have a 25A breaker(MCB - Miniature Circuit Breaker) after the energy meter but before the energy meter normally there is a 25A MCB
(= normally if 3 fase, 1 fase you have 40A in most 230v country's)

An RCD of 40A

The RCD (residual current device or aardlek) has a value of mA (mostly 30mA). The 40A rating is the design current and not a protection grade.

And if your solar system is correctly installed it is connected to its own RCBO(aardlekautomaat). The value of this RCBO depends on the power your inverter can produce.

Yes and no, if your solar is under 500w there is no law that states you have to have a separate MCB and you can plug it straight into a wallsocket.
Over 500 watt a separate line to the fuse box with his own MCB is mandatory ,the MCB is there only to protect the line against overload and shortage.

An RCD is still a debatable issue but to my nowledge (at least till last year) is not yet mandatory.
An RCBO is a MCB and a RCD in one housing and is for safety best practice to use for your solar but is not mandatory..

Everything stated here by me is from the perspective of Dutch rules and regulations

I do like your overview from the P1 meter! Did you use any scripts

Thanks,
Its all scripted, to compute the values and to make the values after comma dissapear(I don't like decimals like with the 'Zon - total energy' one)

example: to calculate home usage F1(Werkelijk gebruik huis L1) = KWH meter F1 + solar F1)

@RonkA,

I followed your discussion and more or less the most you said is true, except 1 thing.

You wrote:

Yes and no, if your solar is under 500w there is no law that states you have to have a separate MCB and you can plug it straight into a wallsocket.

This was indeed the case in the old NEN 1010.
When NEN 1010:2015 became mandotory in 2017 it is no longer allowed and so every inverter, regardless of the produced current should have its own circuit breaker.

Earthing of the solar panels is not required, as they are double isolated, but the metal construction part should be earthed.

Ow, how stupid from me. Ofcourse the C25A (or D25A) device before the meter.

The 30mA did I forgot to mention, sorry.

And the RCBO is not yet mandatory but is the safest way to be installed. So, in my opinion, "mandatory". If I am correct it will become mandatory with the NEN1010 2020 edition.