Category: Metering and energy

The classic EM and 3EM work; the EM Gen3 does not, because the integration reads one specific API. Where each clamp goes, and why it needs a fixed IP.

Between 1 and 1.5 A is 2-3% of full scale on a 50 A clamp. The check that tells the device’s limit apart from a wiring fault.

The 9 mm opening, the cross-section versus diameter mix-up that causes most returns, and how it differs from the Pro 3EM.

Why it powers from phase C, what the 30 VA threshold means, and what the phase-sequence error is actually telling you.

How far it measures, why a 2 A relay cannot take a water heater, and what accuracy to expect. The questions that come up most, with the figures.

With solar panels, the question that matters is not how much they produce. It is how much of it you keep, and how much goes to the grid at less than you later pay to buy it back. The inverter usually shows you production only, and the utility sends the figures days late. The Shelly…

The Shelly EM is showing consumption that looks nothing like the utility meter, or is simply absurd. Before sending anything back: in the great majority of cases the unit is fine, and what is wrong is a detail of the installation or the configuration that takes five minutes to correct. Understanding how it measures explains…