Support for the new Sonoff POWCT

[veno77]

Hello,
Sonoff have new POW Ring Smart Power Meter - POWCT based on ESP32. When can we expect template in the firmware?
Thanks,
Veno

[barbudor]

When you will have purchased one and teared it open to find out the connexion

The team doesn't have the budget to purchase each and every new device in the market, community has to do its part of the job

[rothlive]

I have purchased one.
I could test a new firmware.

[arendst]

From the pictures it seems to me all hardware is already supported by tasmota. All you have to do is finding out which esp32 gpio connects to what chip. Then make the template.

[arendst]

For testing perform the following:

• Load default tasmota32.bin binary supporting all needed hardware.
• Load the Sonoff THR16 template and check if the display works. If not try next
• Load the Sonoff POWR316 template and check if the display works.
• Find the correct GPIOs connected to CSE7761 Rx and CSE7761 Tx

[rothlive]

How can I find out?
With https://templates.blakadder.com/sonoff_THR316D.html
Display -- comes on briefly at startup. Then goes off again
Relay switch works.
GPIO21 | Relay 1

https://templates.blakadder.com/sonoff_POWR320D.html
Nothing works.

[rothlive]

CSE7761 Rx CSE7761 Tx find.
Only enter everything once from GPIO00 to 39 or is there a system for finding this?

[arendst]

"simply" follow the print copper wires from the cse7761serial connection to the esp32 gpio. As the display is connected like a thr316 you might want to chk gpio25 and 26 first being the "normal" thr316d sensor gpios

[rothlive]

"simply" follow the print copper wires from the cse7761serial connection to the esp32 gpio.

I don't know that.
I'm not very familiar with the circuit board.
Can't you see that from the pictures?

[tiagofreire-pt]

From the neighbor next door, all the GPIO configuration: https://devices.esphome.io/devices/sonoff-powct/

[rothlive]

Thank you !

[arendst]

So using the latest dev branch (v14.1.0.3) and this template:

{"NAME":"Sonoff POWCT","GPIO":[32,0,0,0,0,9280,0,0,0,320,0,576,0,9184,9216,0,0,224,0,9248,0,7329,7296,0,0,0,0,0,0,0,0,0,0,0,0,0],"FLAG":0,"BASE":1}

It should work.

NB. Latest dev branch supports single channel CSE7761 when gpio is CSE7761 Rx2 as configured in above template.

[rothlive]

dspline1 11,3,3,4 and dspline2 12,3,6,4 works fine.
Display works perfect.

[rothlive]

Then you can make a new Tasmota Relase with support for the Sonoff POWCT.

[arendst]

Try latest dev from 16:51 which contains the display fix. No need for DspLine anymore.

Next release will be in mid August.

[rothlive]

Ok
This is not necessary even after restarting the display remains functional. I don't have to enter the command again

[rothlive]

I am very pleased that the Sonoff now works with Tasmota.
Many thanks for your help.

[ajaypala]

Does Tasmota support the 2nd current input channel on the CSE7761? I'm wondering if I can add C37, R16, R11, C36, J8 and connect a 2nd Current ring sensor.

[arendst]

The second current ring only makes sense as the ct is used on the same phase. The cse7761 driver already supports two channels like the dualr3. The display driver supports the second channel with dspline commands. Good luck.

[tiagofreire-pt]

How could be used that second display driver channel? The dspline command is highly undocumented. Could you help?

[arendst]

 * DspSpeed 2..127 = Display rotation speed in seconds if more than one value is requested
 * DspLine<1|2> <index>,<unit>,<index>,<unit>,... = Display specific JSON value and rotate between them
 *   unit 0 = None
 *        1 = Temperature (Line 1 only)
 *        2 = %RH (Line 2 only)
 *        3 = Both V (Line 1 only) / A (Line 2 only)
 *        4 = Both kWh (Line 1 only) / W (Line 2 only)
 * DspLine1 0 and DspLine2 0 = Default of temperature/humidity
 * DspLine9 = Show sensor data
 *
 * Example: {"SCD30":{"CarbonDioxide":746,"eCO2":727,"Temperature":30.6,"Humidity":43.6,"DewPoint":16.8}}
 *   index:   1        2                   3          4                  5               6
 *    unit:   0        0 (ppm)             0 (ppm)    1 (C or F)         2 (%RH)         1 (C or F)
 *
 *   DspLine1 4,1,3,0 = Temperature and eCO2
 *   DspLine2 2,0,5,2 = CarbonDioxide and humidity

[arendst]

Latest dev v14.1.0.3 provides an updated version of the CSE7761 energy driver used by Sonoff POWCT. The template has also been finalized as being

{"NAME":"Sonoff POWCT","GPIO":[32,0,0,0,0,9280,0,0,0,288,0,576,0,9184,9216,0,0,224,0,9248,0,7329,7296,0,0,0,0,0,0,0,0,0,0,0,0,0],"FLAG":0,"BASE":1}

The configuration is also available as Auto-configuration.

Using a kind of "reverse engineering" the correct CSE7761 init for Sonoff POWCT has been recorded using below set-up:

[tiagofreire-pt]

Hi, @arendst

On dev 14.1.0.3 and dev 14.1.0.4, the instantaneous power at the display seems to be with scientific notation.

[arendst]

Not according to the changelog:

- ESP32 TM1621 number overflow from "9999" to "12E3" (#21131)

Although it shouldn't do it for values below 9999.... Can you find out what the non scientific number would have been? Is it 4000 or 40000?

EDIT: I see. It is 3619.1 rounded to 40E2. Not good. I'll see how to get rid of decimals first before showing scientific numbers

[tiagofreire-pt]

Thanks for your kind support.

I recommend that the device should show on the display, using scientific notation, for power values above 9999 W, as it's limited to 4 digits. And the device supports up to 23000 Watt (23 kW - 23E3 W)

For lower than 1000 W, would be awesome to get with a decimal, such as 66.7 or 999.9 W. Is this possible?

[tiagofreire-pt]

For both upper examples shown of the issue:

36xx W -》36E2 W
40xx W -》40E2 W

[arendst]

Try latest dev branch where it is fixed now.

Thx for reporting.

[tiagofreire-pt]

Works flawlessly now! Thanks!

[tiagofreire-pt]

Could help on why this meter does not count and measure low power loads, about 5W, displaying 0W?

Is there a setting I'm missing on Tasmota?

[arendst]

As the CT provided is for 100A my guess it won't detect a load below 5W. You'll need a smaller CT for that (which sonoff doesn't provide).

[tiagofreire-pt]

Could you confirm if it's a driver limitation? Because the manufacturer states a range of 0-100A.

[tiagofreire-pt]

Not even setoption39 to 0 makes a difference.

[arendst]

As said, it's a hardware limitation. Also as said by the manufacturer, it supports from 0 to 100A. They don't tell you it cannot detect current changes in the milliamperes needed to detect changes below 5W Hence the existence of 10A, 20A, and 50A CT's.

Search google and learn the CT functionality.

[tiagofreire-pt]

Is it possible to adjust the sensibility of the ADC to others CT, with Tasmota?

[arendst]

It probably is possible. See below excerp from the CSE7761 driver:

/*
    System Control Register (SYSCON)  Addr:0x00  Default value: 0x0A04
    Bit    name               Function description
    15-11  NC                 -, the default is 1
    10     ADC2ON
                              =1, means ADC current channel B is on (Sonoff Dual R3)
                              =0, means ADC current channel B is closed (Pow CT)
    9      NC                 -, the default is 1.
    8-6    PGAIB[2:0]         Current channel B analog gain selection highest bit
                              =1XX, PGA of current channel B=16 (Sonoff Dual R3)
                              =011, PGA of current channel B=8
                              =010, PGA of current channel B=4
                              =001, PGA of current channel B=2
                              =000, PGA of current channel B=1 (Pow CT)
    5-3    PGAU[2:0]          Highest bit of voltage channel analog gain selection
                              =1XX, PGA of voltage U=16
                              =011, PGA of voltage U=8
                              =010, PGA of voltage U=4
                              =001, PGA of voltage U=2
                              =000, PGA of voltage U=1 (Sonoff Dual R3 / Pow CT)
    2-0    PGAIA[2:0]         Current channel A analog gain selection highest bit
                              =1XX, PGA of current channel A=16 (Sonoff Dual R3)
                              =011, PGA of current channel A=8
                              =010, PGA of current channel A=4
                              =001, PGA of current channel A=2
                              =000, PGA of current channel A=1 (Pow CT)
*/
    if (CSE7761_MODEL_POWCT == CSE7761Data.model) {
//      Cse7761Write(CSE7761_REG_SYSCON | 0x80, 0x0A00);  // Pow CT
      Cse7761Write(CSE7761_REG_SYSCON | 0x80, 0xFE00);  // Pow CT - Tasmota (enable B)
    } else {      
      Cse7761Write(CSE7761_REG_SYSCON | 0x80, 0xFF04);  // Sonoff Dual R3
    }

Notice the current gain difference between the dualR3 and the CT.

If you compile your own, play with the value and see if it solves your low power issue (and probably introducing unavailable 100A detection).

[tiagofreire-pt]

If those gains could be set dynamically, through a setoption on tasmota, such as the setoption39, would be awesome. Because compiling the code is not a friendly user way and not practical if you want to remain updated with the latest tasmota release versions.

Do you mind taking a closer look into that?

[arendst]

No unless it makes sense. The current settings are the provided ones from Sonoff to be used with their hardware. Adding user support for changing registers opens a can of worms as there are many options to consider and most of them have no impact at all.

I suggest you make some changes to the current gain and see if it makes sense at all. Again, there won't be many users wanting this except the video kids which seem te be unable to think and just try changes without understanding what they're doing.

[tiagofreire-pt]

If possible, at least, within the dev version as a debug tool to find a better value.

[pluk77]

Thank you so much for the hard work.

For those wanting to do the same:

I flashed my POWCT using the web installer using Edge. It worked but it could not complete the installation. In the browser console I saw the following message coming up:

Improv initialization failed. Error: Improv Wi-Fi Serial not detected

I then cycled the power and had to connect to the wifi of the device to setup the wifi. (All by providing power via Serial Programmer / USB, not mains)

Thereafter I used the auto-configuration option, selected POWCT and the device is working!

Device info according to esptool:

   Chip is ESP32-D0WD-V3 (revision 3)
   Features: WiFi, BT, Dual Core, 240MHz, VRef calibration in efuse, Coding Scheme None
   Crystal is 40MHz
   MAC: e8:6b:ea:f4:ad:34