Power calibration for split coil current sensor (transformer)

[rodajc]

PROBLEM DESCRIPTION

First of all a big compliment to the creators of Tasmota. What a great idea and very well developed.

Now, I modified a Power Monitoring Module to enable the application of a split coil current sensor (transformer). The reason is that this current sensor can easily be clamped on the cable to monitor. In this way the total home power can be monitored by clamping the split coil on the cable going to the distribution panel without changing any wiring or interruption of any kind.
A more detailed description can be found here: #22794

These current sensors are very cheap. Therefore their application can be expected to rise. This would increase the need for a small adaptation to Tasmota to correct the current and therefore the power measurement result. The reason is that the current sensor doesn't detect currents below a certain level because of the magnetic characteristics of the transformer coil.

I would propose two new commands: CurrentOffset (mA) and PowerOffset (W). Both these commands would accept one parameter. The value passed to these commands would be added internally to the current and power measurements. Irrespective of their value, high or low, the same offset would be added. In my case passing 250 mA to CurrentOffset and 57 W to PowerOffset would do the trick.

Your ideas please.

REQUESTED INFORMATION

Make sure your have performed every step and checked the applicable boxes before submitting your issue. Thank you!

• Read the Contributing Guide and Policy and the Code of Conduct
• Searched the problem in issues
• Searched the problem in discussions
• Searched the problem in the docs
• Searched the problem in the chat
• Device used (e.g., Sonoff Basic): Sonoff Pow
• Tasmota binary firmware version number used: 13.4.0
  • Pre-compiled
  • Self-compiled
• Flashing tools used: esptool 4.7.0
• Provide the output of command: Backlog Template; Module; GPIO 255:

  Configuration output here:

13:48:57.687 RSL: RESULT = {"NAME":"Sonoff Pow","GPIO":[32,0,0,0,0,2592,0,0,224,2656,2688,288,0,0],"FLAG":0,"BASE":6}
13:48:57.916 RSL: RESULT = {"Module":{"0":"Sonoff Pow"}}
13:48:58.170 RSL: RESULT = {"GPIO0":{"32":"Button1"},"GPIO1":{"0":"None"},"GPIO2":{"0":"None"},"GPIO3":{"0":"None"},"GPIO4":{"0":"None"},"GPIO5":{"2592":"HLWBL SEL"},"GPIO9":{"0":"None"},"GPIO10":{"0":"None"},"GPIO12":{"224":"Relay1"},"GPIO13":{"2656":"HLWBL CF1"},"GPIO14":{"2688":"HLW8012 CF"},"GPIO15":{"288":"Led1"},"GPIO16":{"0":"None"},"GPIO17":{"0":"None"}}

• If using rules, provide the output of this command: Backlog Rule1; Rule2; Rule3:

  Rules output here:

13:51:02.335 RSL: RESULT = {"Rule1":{"State":"OFF","Once":"OFF","StopOnError":"OFF","Length":0,"Free":511,"Rules":""}}
13:51:02.568 RSL: RESULT = {"Rule2":{"State":"OFF","Once":"OFF","StopOnError":"OFF","Length":0,"Free":511,"Rules":""}}
13:51:02.817 RSL: RESULT = {"Rule3":{"State":"OFF","Once":"OFF","StopOnError":"OFF","Length":0,"Free":511,"Rules":""}}

• Provide the output of this command: Status 0:

  STATUS 0 output here:

13:52:57.414 CMD: status 0
13:52:57.421 RSL: STATUS = {"Status":{"Module":0,"DeviceName":"Tasmota","FriendlyName":["Tasmota"],"Topic":"tasmota_3B79FF","ButtonTopic":"0","Power":1,"PowerOnState":4,"LedState":0,"LedMask":"FFFF","SaveData":1,"SaveState":1,"SwitchTopic":"0","SwitchMode":[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],"ButtonRetain":0,"SwitchRetain":0,"SensorRetain":0,"PowerRetain":0,"InfoRetain":0,"StateRetain":0,"StatusRetain":0}}
13:52:57.427 RSL: STATUS1 = {"StatusPRM":{"Baudrate":115200,"SerialConfig":"8N1","GroupTopic":"tasmotas","OtaUrl":"http://ota.tasmota.com/tasmota/release/tasmota.bin.gz","RestartReason":"Power On","Uptime":"12T21:01:36","StartupUTC":"2025-01-10T15:51:21","Sleep":50,"CfgHolder":4617,"BootCount":21,"BCResetTime":"2024-03-01T17:23:13","SaveCount":438,"SaveAddress":"F6000"}}
13:52:57.431 RSL: STATUS2 = {"StatusFWR":{"Version":"13.4.0(tasmota)","BuildDateTime":"2024-02-14T16:13:56","Boot":31,"Core":"2_7_6","SDK":"2.2.2-dev(38a443e)","CpuFrequency":80,"Hardware":"ESP8266EX","CR":"302/699"}}
13:52:57.435 RSL: STATUS3 = {"StatusLOG":{"SerialLog":2,"WebLog":2,"MqttLog":0,"SysLog":0,"LogHost":"","LogPort":514,"SSId":["casillas",""],"TelePeriod":300,"Resolution":"558180C0","SetOption":["00008001","2805C80001000600003C5A0A192800000000","00000080","00006000","00004000","00000000"]}}
13:52:57.445 RSL: STATUS4 = {"StatusMEM":{"ProgramSize":646,"Free":356,"Heap":24,"ProgramFlashSize":1024,"FlashSize":4096,"FlashChipId":"1640EF","FlashFrequency":40,"FlashMode":"DOUT","Features":["0809","8F9AC787","04368001","000000CF","010013C0","C000F981","00004004","00001000","54000020","00000080","00000000"],"Drivers":"1,!2,3,!4,!5,!6,!7,!8,9,10,!12,!16,!18,!19,!20,!21,!22,!24,26,!27,29,!30,!35,!37,!45,62,!68","Sensors":"1,2,3,4,5,6","I2CDriver":"7"}}
13:52:57.450 RSL: STATUS5 = {"StatusNET":{"Hostname":"home-power","IPAddress":"192.168.0.117","Gateway":"192.168.0.1","Subnetmask":"255.255.255.0","DNSServer1":"192.168.0.1","DNSServer2":"0.0.0.0","Mac":"2C:3A:E8:3B:79:FF","Webserver":2,"HTTP_API":1,"WifiConfig":4,"WifiPower":17.0}}
13:52:57.456 RSL: STATUS7 = {"StatusTIM":{"UTC":"2025-01-23T12:52:57Z","Local":"2025-01-23T13:52:57","StartDST":"2025-03-30T02:00:00","EndDST":"2025-10-26T03:00:00","Timezone":99,"Sunrise":"08:30","Sunset":"17:32"}}
13:52:57.459 RSL: STATUS9 = {"StatusPTH":{"PowerDelta":[0,0,0],"PowerLow":0,"PowerHigh":0,"VoltageLow":0,"VoltageHigh":0,"CurrentLow":0,"CurrentHigh":0}}
13:52:57.467 RSL: STATUS10 = {"StatusSNS":{"Time":"2025-01-23T13:52:57","ENERGY":{"TotalStartTime":"2024-03-06T22:14:32","Total":4723.073,"Yesterday":22.344,"Today":13.457,"Power":1985,"ApparentPower":1993,"ReactivePower":182,"Factor":1.00,"Voltage":227,"Current":8.781}}}
13:52:57.472 RSL: STATUS11 = {"StatusSTS":{"Time":"2025-01-23T13:52:57","Uptime":"12T21:01:36","UptimeSec":1112496,"Heap":24,"SleepMode":"Dynamic","Sleep":50,"LoadAvg":19,"MqttCount":0,"POWER":"ON","Wifi":{"AP":1,"SSId":"casillas","BSSId":"D8:07:B6:D6:B3:38","Channel":6,"Mode":"11n","RSSI":98,"Signal":-51,"LinkCount":1,"Downtime":"0T00:01:07"}}}

• Set weblog to 4 and then, when you experience your issue, provide the output of the Console log:

  Console output here:

TO REPRODUCE

Steps to reproduce the behavior:

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EXPECTED BEHAVIOUR

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SCREENSHOTS

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ADDITIONAL CONTEXT

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[rodajc]

It would be great to compile a test firmware including the proposed changes.

I would need a hand though. I have compiled firmware before (OpenWrt, AVR microcontrollers, etc..), but I have never used PlatformIO.

[rodajc]

Anyone who is familiar with the source code, how long can it take to implement these two new commands CurrentOffset (mA) and PowerOffset (W) as proposed?