#170 Pulse meter

[mmmichl]

This adds support for pulse meter to indicate the HP the desired power consumption in combination with the smart grid functionality.

Final Usage
Is as simple as the SG functionality, set the desired power usage in MQTT. Value is interpreted in watt. If you use Home Assistant, it will - similar to SG - auto-configure an input field, where you can set the available/desired power usage.

Hardware
I made a board with optocouplers. I measured 12 V - 16 V on the contacts and used the "LTV 815" optocoupler. I am not an electrical engineer, so not sure if this is the right thing, but so far it works. I am using a esp-wroom-32 dev board.
Pulse meter cables were connected to S4S (X5M connections 3&4) connect. Watch for the polarity of the cables, the optocouplers only work when the current flows in the right direction.

Alterma Setting
This is the part where I am still trying to figure out what needs to be set up to respect the pulse meter in "recommended on" state. The pulse meter works - I tested it against an other ESP with esphome pulse meter setup.

Following for sure needs to be set:
[Installer Setting]/[Energy metering]/[Electricity meter 2]: change away from "None". Should be either "1000/kWh" or "1000/kWh for PV panel"

This one setting seemed not be sufficient, so I am still investigating.

For good measures, I have a Daikin Altherma 3 H HT F (ETVH16S23EA9W)

Still open:

• Finish Readme
• Act on to high watt setting, that cannot be safely transmitted (e.g. pulses faster than pulse length)

refs #170

[raomin]

Hey @mmmichl, sorry for the late reply! that's a very nice feature indeed.
I could finish the readme but some implementation pictures would help. Could you please share some here?

[mmmichl]

Hi, I have this code running for some months now, but I want to do some refactoring and I think more documentation before I see this PR finished. Time and Motivation is currently not to kind to me, but good to know, that there is interest in this PR. 😀 Can you explain, what kind of pictures you want to see? The hardware with the optocouplers? Or the connection with the heat pump?

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On Sat, Nov 25, 2023, 00:35 Raomin ***@***.***> wrote: Hey @mmmichl <https://github.com/mmmichl>, sorry for the late reply! that's a very nice feature indeed. I could finish the readme but some implementation pictures would help. Could you please share some here? — Reply to this email directly, view it on GitHub <#310 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAI5AWZMD5O2CXH65DEA6Y3YGEVKZAVCNFSM6AAAAAA3G4J4AGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTQMRWGEZTOOBSGQ> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[lfrancke]

As a novice bystander:
I'd love to see both. As much as possible to reproduce your work. Parts lists etc. would be fabulous.

[gerione]

@mmmichl Did you already get the altherma settings to run?

[mmmichl]

Soo, finally found time to finish things. So far I implemented and document all I was planing to. If you have questions or if things are unclear, let me know.

Still need to resolve the conflicts, or maybe someone wants to do that?

[aav66]

@mmmichl Is any way to check if pulse meter signal is received be HP?
I done it same way as on picture... but not sure if it works. SG1 SG2 signals is updating. But didn't found any way to measure pulse signal.

Also a bit confused about readme and pictures. Is 200 Ohm resistor needed before ground and LT815?

[mmmichl]

@aav66 I am not aware of any easy and reliable way. Best hint I could find, was in the overview image of the heat pump:

the power line on the right and the faint line on the roof representing solar panels seems to be a good give away. The symbol in the circle is either that the heat pump is heating up more than the set temperature, or that is uses the excess from the solar panels - not sure.

As I don't have any reliable values on how much the heat pump consumes, I watched the smart meters import/export. I had the impression, that the heat pump used the excess electricity, as it kind of followed a rising curve of solar panel production. But I think I remember, that it always used more power than available, e.g. the import sat around 500 W, although the solar panels produce more over time. But I might be mistaken. Anyway, as the project took me a couple of months, I settled for "good enough" :)

As for the resistor: I placed it between the LT815, the positive/phase and the heat pump. I got it from the Wiki page bout the pulse meter interface (the page is unfortunately German) but honestly, I don't know if it is necessary.

[spleijers]

Quick question about this, would a pcb like this work for this purpose?

Ali (Klick the 12v version)

I already have relays connected to the SG inputs...

[mmmichl]

As stated, I am not an electrical engineer. It took me some sweaty hands and a long time to wire this rather simple thing up. Also please measure how much volt and ampere your heat pump uses.

So with my limited knowledge, I do say this looks kind of what I did. But I am a bit confused, why there are three connections on the "output" side.

[spleijers]

Yes no worries, I'm also not an electrical engineer so i was hoping someone with more knowledge could verify this. The 12v input should be OK, because i know a S0 Electricity meter can be connected to the S4S port (S0 signal should be 12v).

This image explains better wat it should do. I think the device should be able to 'give 12v pulses' via a ESP32 device. And indeed, the 3rd cable is not necessary it seems. Anyone here that can verify this will work?