Zigbee Smart Meter with fast refresh intervall?

[temmyn (on a steep learning curve)]

I’m using the Zemismart (Tuya) SPM02V3 Smart Meter. It’s working perfrectly, but the fastet configurable update frequency via zigbee2mqtt is 30 seconds.

I know the zigbee protocoll is not designed for high update frequency applications, but still I would like to know if there is a device which might be faster, maybe 10s oder even 5s. Would still be a lot better than 30s.

Or is there even a possibility/hack to let the SPM03V2 update faster?

In the end if there aren’t any options I might switch to the Shelly 3EM Pro, if there isn’t a zigbee alternative but looking to avoid this if there is any chance?

Thanks in advance.

[maxym]

@temmyn

In the end if there aren’t any options I might switch to the Shelly 3EM Pro, if there isn’t a zigbee alternative but looking to avoid this if there is any chance?

If you decide for the Shelly (you will), keep in mind that there are models with very similar form factor to mentioned zemismart. if it does matter for you.

[temmyn (on a steep learning curve)]

Thanks for your response. Could you give me a hint?

I only see the 120A, 63A and 400A version of the Shelly 3EM Pro an they all come with CT clamps, so same form factor for all shelly variants but different than the zemissmart.

The form factor matters indeed. Was already a big hustle to install the Zemismart due to lack of space and the Zemismart has the charme to be quite small, with only 21mm tall. The CT clamps as far as I can tell are about 30-31mm tall, which might lead to issues in my installation scenario.

EDIT:
Apparently the Shelly Pro 3EM 3CT 63 has the same style “clamp” as the Zemismart. But for some reason it is not marked as Zero-feed-in device

[orange-assistant]

@temmyn

But for some reason it is not marked as Zero-feed-in device

Why should an energy meter be marked as “zero-feed-in” device? That’s like as usefulless as marking an electric vehicle as nicotine free

@temmyn

faster, maybe 10s oder even 5s

Our pzem004t-v3 boards ($10 when bought) paired with an esp32 ethernet board is set to 100ms (0.1s) using the esphome native api

Peacefair PZEM-004T V3 Energy Monitor

You find the pzem004t with fixed/closed coils (see photo in the esphome docs) or with bigger clamp coils which you can open/close

[temmyn (on a steep learning curve)]

@orange-assistant

Why should an energy meter be marked as “zero-feed-in” device?

I’,m not sure. I’m not a Know-it-All and thought maybe there is a reason.

Thanks for linking the PZEM-004T Project. Sounds interesting an promising. Maybe I’ll try it in the future, but for my current time shedule it is to much of an DIY project unfortunately (atm)

[Karosm]

@temmyn

it is not marked as Zero-feed-in device

What you mean with this? Marked where?

[temmyn (on a steep learning curve)]

See the screensot. The middle device is not tagged like the others, although it’s supposed to do the same job.

[WallyR (Wally)]

@orange-assistant

Why should an energy meter be marked as “zero-feed-in” device?

CT clamps can not be run safely in an open circuit without a burden transistor, which maybe are missing in that product.

[Karosm]

@temmyn

is not tagged like the others,

If you read the specs, you see they are same for both PRO 3EM models, only clamps are different. Tagged or not.

Shelly Pro 3EM-3CT63

And nothing is missing.

[orange-assistant]

@WallyR

CT clamps can not be run safely in an open circuit

While the non-contact power/energy meters contain current transformers they already come with all necessary circuit - otherwise they would only be current meters

@Karosm

@temmyn

not marked as Zero-feed-in device

What you mean with this?

Translation gone wrong? A non-contact power/energy meter doesn’t/can’t interfere with the power feed

[Karosm]

@orange-assistant

Translation gone wrong?

Not really. Google assisted translator doesn’t give any hint to “zero-feed”:
Energy saving,
performance monitoring
PV systems
charger for electric vehicles

So I have no idea from where that comes from…
For sure Shelly doesn’t backfeed anything.

[temmyn (on a steep learning curve)]

I thought PV System includes intelligent battery management.
Therefor I used the term “zero-feed-in” instead of PV Systems.

[maxym]

@temmyn

I only see the 120A, 63A and 400A version of the Shelly 3EM Pro an they all come with CT clamps, so same form factor for all shelly variants but different than the zemissmart.

There is one more model available. It resembles the zemismart most:

Shelly 3EM-63T Gen3

Regarding zero-feed-in, I would consult Shelly support. Maybe it has something to do with resolution/precision/frequency of measurement reporting. Maybe it’s about modbus protocol some of these devices boast of, while others not etc. Just guessing. The Zero-feed-in requires pretty frequent measurements especially around 0.

[orange-assistant]

@temmyn

I thought PV System includes

Some PV inverter support zero injection/feed-in. For this to work they need to know how much power from the grid is import/exported which is usually done with the help of a power meter (sometimes only a ct) that is connected to the inverter.

You need to consult ■■■ ■■■■■■ of your PV system to find out which power meters are actually supported that can be connected so the inverter can do do zero feed in (only produce as much AC power as requested locally)

[Karosm]

While technically possible, I seriously doubt that some PV inverter out of the box can use Shelly as meter for it’s zero-export feature.

[WallyR (Wally)]

My guess to the zero-feed was like the open circuit warning in the safety section here.

CT sensors - An Introduction

[orange-assistant]

@WallyR

My guess

Makes zero () sense ■■■■■■