Clamp Sensor Energy Monitoring - ESPHome in Home Assistant

That was awesome, great job - thanks for showing, exactly what I wanted.

Followed these instructions to start monitoring my house power, thanks. I think I need to adjust the calibration again as the CT clamp is reporting higher power usage than the electricity meter but even if the absolute values aren't accurate being able to see the relative power consumption between days or when different appliances are on is great.

Thank you for explaining! But there are some remarks about the calibration. First of all I wouldn't recommend a microwave because the fluctuations in the current it draws may be quite substantial. A kettle is way better because it's basically just a metal wire heating up. (Although the current may slowly decrease over time) Also it's better to have some kind of energy monitor to use as a reference. The actual energy consumption may differ quite substantially from what's written on the device. Nevertheless, you made me think of some great new ideas 💡

Will, I enjoy your channel a lot but you are wandering into an area that you don’t fully understand. Apart from the inaccuracies in the power measurement as set out by other comments, there is a major safety concern here. The CT clamp used here does not have a burden resistor before the jack plug, it has one on the board, so if the plug was to be removed while measuring it would lead to dangerously high voltages at the jack plug. A burden resistor should always be installed as close as possible to the CT itself. Split core CT’s are available with a resistor installed with the output in millivolts which is a much safer choice in this arrangement . You should consider pointing to the dangers of using this type of arrangement on this video. Safety is a priority.

Thanks for sharing this neat idea, I just bought the parts using your links :-) two things I will say: 1) I thought mains voltage here in the UK was more commonly 240v, I know when I measure it within my house it is 240v. Also 2) I thought perhaps a micro-wave isn't the best appliance to measure, not only because of the WiFi interference, but also because the load/demand isn't always on, a Microwave pulsates using higher wattages here and there for a few seconds, then gives a break etc. I think something that may give a bit more of a predictable load (like perhaps a kettle) might be better. Thanks for a great vid though.

You are on the top. Thank you so much. Greetings from Athens.

Great work Will!

Thanks for this. I have struggled a bit with this in Home Assistant / ESPHome for the last month. Your video was really useful and well explained. Many thanks

Hi Will, thanks for this vid. I'm getting some odd behaviour, I calibrated mine with the immersion heater, known load, and compared results with a Shelly EM and the power measurement was within a few watts. Happy. I turned the immersion off and normal background power use for the house went to 160w ish. however the esp/ct didn't go below 300w. I took the clamp off the mains feed and measured nothing but I'm still getting a reported current and watt usage. log extract below. [11:57:09][D][ct_clamp:037]: 'Measured Current' - Raw AC Value: 0.000A after 3 different samples (15 SPS) [11:57:09][D][sensor:126]: 'Measured Current': Sending state 0.13084 A with 2 decimals of accuracy [11:57:10][D][sensor:126]: 'Measured Power': Sending state 0.03102 kW with 1 decimals of accuracy [11:57:10][D][sensor:126]: 'Total Daily Power': Sending state 143.78992 kWh with 3 decimals of accuracy any ideas why 0A is showing as 0.13084A here's the config used captive_portal: sensor: - platform: ct_clamp sensor: adc_sensor name: "Measured Current" update_interval: 5s id: measured_current filters: - calibrate_linear: # Measured value of 0 maps to 0A - 0 -> 0.000 # Known load: 5.0A - change this! # Value shown in logs: 0.01229A - change this! - 0.040 -> 12.377

Bravo , thank you , you are great.

thanks so much for this video... your clip is the only one I could find that then shown us how to add the entity to Home assistant grid consumption and I've been looking for days! as other examples of Yaml files the entity doesn't show up in energy tab...subbed

Good video mate. Thanks

Hi Will, and great video! Is there a way to connect two CT clamps up to a D1 mini? Thanks, Joe

Hi, great video, all configured and working however my homeassistant values are about 5kwh per day above meter usage. I used the single port motram board with SCT013 100A 50ma CT. Calibrated using a 2000w wallpaper stripper to calibrate. Is there anyway to recalibrate adjust code to get a more accurate reading using a CT . ? Thx in advance

Hi Will, thanks for the video. Was wondering why you'd put the clamp around only the live wire rather than just the whole power cable? struggling to get meaningful results out of my attempt at this project.

Great video, I have a Shelly that measures the voltage, could you use the voltage measurement instead of theoretical values?

Any ideas why I get negative A / W readings after I enter these calibrated values (@240v)? filters: - calibrate_linear: # Measured value of 0 maps to 0A - 0 -> 0 - 0.01780 -> 4.72 # 1134w microwave (700w) - 0.03571 -> 11.26 # 2702w kettle (2520-3000w)

Will quick question! Can I put this around my whole home live wire and measure the houses energy consumption?

The schematic of pcb is not clear could you give a higher resolution link please

Whats was the neatest way to supply the usb power to wemosd1 when its in the meter cupboard