Hi, my setup is working Okay and is repeatable, just trying to find a way to offset the zero.
So In my configuration I added another sensor to monitor the raw reading when I have the calibrate linear filter applied to the main Measured Current…
- platform: ct_clamp
sensor: adc_sensor
name: “raw values”
If you look at your logs you will see for example 0.01801 represents 6.42298 A, this is implemented in the filters, - calibrate_linear:
forget using the adc_sensor for your reading.
[14:15:52][D][sensor:092]: 'adc_sensor': Sending state 0.41895 V with 2 decimals of accuracy
[13:49:04][D][sensor:092]: ‘raw values’: Sending state 0.01801 mA with 5 decimals of accuracy
[13:49:07][D][ct_clamp:051]: ‘Measured Current’ - Raw Value: 0.02A
[13:49:07][D][sensor:092]: ‘Measured Current’: Sending state 6.42298 A with 2 decimals of accuracy
[13:49:14][D][ct_clamp:051]: ‘raw values’ - Raw Value: 0.02A
[13:49:14][D][sensor:092]: ‘raw values’: Sending state 0.01807 mA with 5 decimals of accuracy
My config, I added the "raw values so I could log the values easier.
sensor:
- platform: ct_clamp
sensor: adc_sensor
name: "Measured Current"
update_interval: 10s
filters:
- calibrate_linear:
- 0.0 -> 0
- 0.01826 -> 5.15
- 0.01952 -> 6.754
- 0.01925 -> 7.09
- 0.04057 -> 16.02
- 0.07834 -> 31.37
- platform: adc
pin: 17
id: adc_sensor
- platform: ct_clamp
sensor: adc_sensor
name: "raw values"
update_interval: 10s
unit_of_measurement: mA
accuracy_decimals: 5
My setup for the initial calibration.
Portable electric heater with low (3.5 A) and high (6.9 A) low/high selector, CT and Multi meter in series measuring amps.
so taking the reading from the logs and then writing the linear values in the configuration gives a good repeatable reading.
My issue is when the load is zero i get an erratic reading. drifting between 0.2 a 0.5 A.
For the higher calibration values i transferred my setup to measure the main incoming supply to the house.
I then was able to put increased loading on the the CT as my Fluke can measure 10 Amps max,
With this I was able to calibrate the higher loads,16 A and 31 A by comparing readings from my smart meter and the readings from the log and modified the calibration linear table accordingly.