Shelly Pro 3EM or ZemiSmart 120A?

What three -phase energy meter do you recommend to measure the total consumption of the 3 phases? The Shelly is Wifi and the Zemismart is Zigbee, and could integrate it with Zigbee2MQTT or with Tuya’s integration. It would be to know consumption and power.

Cannot give you definite answer. especially because I don’t have the ZemiSmart. but let me write down several key points.

  • if you chose shelly Pro 3EM-3CT63 it has very interesting solution for current transformers. standard ones are incredibly bulky
  • the Shelly has built-in Ethernet port
  • the Shelly can be used as BLE gateway
  • I doubt zigbee devices provide as many configuration options as the shelly
  • I’m not sure Zigbee is designed to transmit real-time data. using such a device can possibly impact your zigbee network performance. Check how frequent Zigbee device updates data
  • with the shelly you can chose between native integration or mqtt (manual or discovery script). With zigbee there is native integration and zigbee2mqtt. You need to check which one supports the device.

Personally i would go for the Shelly.

Another vote for Shelly.
In addition to above, 5yr warranty, works locally out of the box, certified european product, very accurate.

1 Like

You can configure this using Reporting in Z2M, but still - go for the Shelly.

hi
@maxym
can u elaborate here what do u mean by 3Ct64 and standard ones? by standard ones u mean Shelly Pro 3EM 120A?

is there a way that Shelly can sense somehow what kind of devices are on wires and how many W they consume?

thanks!

Here is “standard one” Pro, with clamps.

And here is 3CT63, offering a different form factor current transformer. It might be handy. But it is limited to 63A combined (by docs), while standard clamps allow measurement up to 120A or 400A per line.

There is also another interesting model, where electronics are packaged together with coils. There are two versions of this piece, with flat terminals (on picture) or with cables.

is there a way that Shelly can sense somehow what kind of devices are on wires and how many W they consume?

When it comes to consumption, this term is more common for energy (Wh). However, Shelly devices also report instantaneous power (W), though of course this depends on a finite sampling rate.

Regarding your question about the “type of device,” I’m not entirely sure what you meant. But most Shelly energy meters do report the power factor (PF), which can be used to differentiate between resistive and inductive loads.

hi @maxym
okay so in case i have 3x25A … 75A total … i cant use that one?

still no clue whats diff between 3CT63 vs PRO

thanks

To my opinion yes. Combined 63A doesn’t make any sense electrically here, they are separate channels.
“single or three-phase energy meter with a combined 63A, 3-phase current transformer.”
“Combined” in this context means that the CTs are in one block.

@karosm sorry i dont get it …

if i have 3x25A can i use that 63A one?

thx

Yes.
But I personally would go with Pro 3EM for flexibility.

@karosm thanks
what flexibility is on your mind?

but in full load of 3x25A … 63A wont be able monitor it, right?

thx

Flexibility of installation.
Anyway, it has 3 channels, each for 240V/63A.

which one are u referring to? seems 120A per Phase ?

How can I make it more clear…
[
Shelly Pro 3EM 3CT 63 has 3x63A current transformers in one block.
Shelly Pro 3EM has 3x120A separate clamps.

In your case pick the one more adapts your physical wiring, that monoblock doesn’t stretch anyhow.

The whole concept of “combined” doesn’t exist in electric wise!

no idea why it was discussed /described as “combined”.