Questions regarding SCT-013 and AC current sensing

[deanfourie (Dean)]

I’m looking at getting my hands on a few of these SCT-013 current sensor clamps

1Pcs SCT - 013 - 050 Non - invasive AC Current Sensor Clamp Sensor 50A |...

My question is, how much modification is required to integrate this with an ESP32 and esphome? Voltage deviders etc?

Also, if voltage deviders are required, do they need to be altered with each different current measurement? eg, 20A 50A 100A etc.

Anyone using these with an ESP32?

Thanks!

[orange-assistant (the real one)]

@deanfourie

looking at getting my hands on a few of these SCT-013 current sensor clamps

Can I ask what for? Are you really interested in current (and not power) for your scenario?

@deanfourie

Anyone using these with an ESP32?

Many did and many found out that they actually want to measure power and not current

Home built energy monitor using ESP8266 doesn't see small loads

You probably build a (maybe) somewhat accurate current meter. But what you actually wanted was a accurate power meter (your energy is billed on that). We learned: A current meter can not substitute a power meter (in AC scenarios when PF ≠ 1)

Will Low Cost ESP8266 4 Channel Power Monitor Work With ESPHome?

The headline “Will Low Cost ESP8266 4 Channel Power Monitor Work With ESPHome?” is actually misleading. The website states that the product shown in the picture from @Jonah1970 is actually a “ESP8266 - 4 Channel Mains Current Sensor” Accurate power measuring will be impossible with that type of device The blue uses the internal ADC from the esp while the green board uses a (better) ads1115 - still both only measure current and not power Does it matter at all? Wha…

Schematic for ct clamp, ad1115, esphome

No but plenty of results when I google it for you (including plenty of results in this community ) In case you want to actually know your (AC, PF<1) power or energy consumption a ct clamp will not be sufficient as it will only output current

Energy Tracking - CT Clamp Current Sensor

Can it be enough to know the rms voltage and the current at the same time without taking the power factor into account to be able to distinguish between active (kW) and reactive (kVAR) power? Doesn’t the rms voltage and current only allow you to get the apparent (kVa) power? That would be a indication that you only measure the apparent power and not the active power that you are pay for The change is rather high that when you use a higher power device th…

@orange-assistant

Well the problem with CT clamps (a current meter) is that you can’t just “convert” it to power by multiplying it with the voltage. Without taking the power factor into account you will not be able to get “real” values.

@deanfourie

My question is, how much modification is required to integrate this with an ESP32 and esphome?

CT Clamp Current Sensor