Some questions regarding 3EM (FAQ)

There is too much outdated information or not completely coherent answers regarding these questions.

I've selected (bottom) some of the topics and their answers, as well as some of the official documentation to try to answer the following questions, but some remain unanswered (??) or with an incomplete answer.

I would like clarify some FAQ of this product not yet "answered" as of 2023/06 (Firmware 20230510-083155/v1.13.1-gda6f9f2)

What is the minimun polling time of 3EM?

??

How does the 3EM handle non-linear loads i.e: inverter, pc-power supplies etc?

??

What is the accuracy/precision of the measurements? Do they comply with any standard?

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Some topics state 1% accuracy (other people describe it as precision...) but do not clarify if in voltage, current or phase and if its related to nominal values or any other reference value.

EN 50470-1 for reference.

After all most people, IMHO, would be satisfied to know the expected deviation/error in energy mettering per month f.e. in +-kWh, to compare with their bill.

Can 3M handle a 4th current clamp for the neutral conductor and show its data as a normal channel?

It can handle the 4th clamp for sure if its 120A model.

Regarding data collection N is not considered as a fourth channel in the interface.

??

Which is the correct accessory for 3EM the 120A, the 50A or both clamps?

Some topics state that the 50A is not compatible with the 3EM, but the box of the 50A clamp states its an accesory for 3EM.

The following link states that "other transfoerms may destroy the device" but some topics describe other transformers as compatible and secure.

https://www.shelly-support.eu/lexikon/entry/353-3em-calibration-of-the-n-clamp/

If the 50A clamp is compatible, which is the reference, part number, specifications for the 4 pin connector? (50A comes with bare wire)

??

How can the neutral current clamp work ("uncalibrated") as an accessory but the provided current clamps are "factory calibrated" and are not interchangable? Does the accesory come with a calibration file?

3EM provides a current calibration system in its webserver. Instructions are in the LEXICON of this site.

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Is the energy (power*time) data logging (In/out) corrected or you still need a third party software to compute it?

??

Related topics with no "clear answers":