[BK7231N] Teardown Action LCS Smart Plug (with Energy Meter) 3202087

OBK config:


Added after 13 [minutes]:

Added, thank you:
https://github.com/OpenBekenIOT/webapp/commit/6b2b0c0fd57f1b99a3bbf2a88d073ffe651e46c4

Hi,
Thanks for the info. How did you open it without breaking the housing?

Ok, found it: The hooks that hold it together are in the corners. So you have to press the edge on the side of a table at a 45° angle and then push on the left or right ground surface with a screwdriver.

In each corner on the back, there is a clip. I used a slim metal blade to force it a bit.

Hello everyone,

I also received the sockets today. Unfortunately, it is not possible for me to flash these with the Tuya Cloudcutter OTA. Which profile should you choose? The Tuya firmware is V1.1.17.

Thanks in advance!

AFAIK, it is not in the profiles yet. I simply entered the settings listed in the JSON.
In "BK7231 Easy UART Flasher," I used the button "change obk settings for flash write" and edited the details before flashing,
switched "Automatically extract Tuya..." and
"Do firmware backup" off
and then it worked.
I struggled a bit to get the flash process going under Linux. When you reset by "power off," Linux loses the UART port setting, and the CEN input somehow didn't do what I expect. For me, it is still unclear how to enter flash mode - it worked at one point, but I cannot say what I did.

Dobie01 wrote:

Afaik it is not in the profiles yet. I simply entered the settings listed in the json.

If you are referring to OBK profile, it seems to be here:

Dobie01 wrote:

When you reset by "power off" Linux looses the UART port setting

Have you watched our tutorial videos? We have videos one per each device type showing the process:
https://www.youtube.com/@elektrodacom
By "power off", we mean that you need to disconnect you 3.3V from WiFi module (or 12V from LED strip). This will not work if you disconnect from USB to UART converter, because then COM port will diseappear.
Also make sure to use good quality power supply, because in some rare cases, if you power device from 5V (to use onboard LDO regulator to get 3.3V), and you reset by disconnecting that 5V wire from USB, this may still cause UART port diseappear because you overload the USB port with too large inrush current

Dobie01 wrote:

AFAIK, it is not in the profiles yet. I simply entered the settings listed in the JSON. In "BK7231 Easy UART Flasher," I used the button "change obk settings for flash write" and edited the details before flashing,

Thanks for the information. It's a shame that it's currently not possible to flash these sockets OTA. Unfortunately, I don't have the time for soldering work at the moment. I tried to create a custom profile in the tuya cloud cutter using the JSON data. Unfortunately, I failed.

Don't lose too much time trying. This firmware version 1.1.17 is using the SDK 2.3.3 that is patched. Cloud cutter will not work with it.

It's easy to flash with wires, even if socket is hard to open. Here's how I handled one like that:

It's just import to secure the hole later.

setheal74 wrote:

Don't lose too much time trying. This firmware version 1.1.17 is using the SDK 2.3.3 that is patched. Cloud cutter will not work with it.

Thanks for the hint. I honestly didn't realize that.

p.kaczmarek2 wrote:

It's easy to flash with wires, even if socket is hard to open. Here's how I handled one like that:

Fortunately, the LSC sockets are not glued and can be opened easily. Do you have a tutorial for flashing using a USB to TTL serial adapter? Thanks in advance!

We have many tutorials for that, here are two examples, N platform:

T platform:

Hello everyone,

today I successfully flashed said sockets to openbk using a USB to TTL converter.

The whole thing worked without soldering using jumper cables and test hooks. If you are interested, here is the link and two more pictures:

https://amzn.eu/d/c8j3XUQ

Great Tip !
Just ordered those too !

Hinzugefügt nach 4 [Minuten]:

Just managed yesterday to also flash one by myself.
But I am personally using ltchiptool on debian cli myself to flash.
Worked perfect.

Sensors have to be created a bit different than the profile suggest since the Voltage divider is wrong set and the second led is not created out of the dump.



and

dingsundbums wrote:

Sensors have to be created a bit different than the profile suggest since the Voltage divider is wrong set and the second led is not created out of the dump.

The simplest way to get it automatically configured is to use our OBK Web App config extraction:

Thanks to this, you can get GPIO config directly from Tuya partition. It's always better than guessing.

Anyway, it's good to hear you got that working in your way.

Did it with a dump to get the pinout. Worked too.
As said: only Voltage divider was wrong.

I have just spontaneously registered here to add some more information. Maybe it will help some successors. Thanks also for the help I found here.

"Action" in Germany still has some of these sockets on sale and as they are the cheapest with energy metering I could find, I thought I'd give them a try. Disassembly also seemed to be simple...

However, I didn't find it quite so easy and "carved" four wedges from a credit card to release the tabs in the corners of the housing. I had to use another credit card and a pair of pliers to get them inserted. In the pictures you can see where they finally went in with some difficulty and a lot of wiggeling.



In fact, the power supply from the CH340 adapter was not sufficient, but an existing breadboard power supply solved the problem quite easily, especially as it has its own switch. I also followed the tip with the mini terminals. Again, hopefully the photos show enough detail. The power was injected at the terminals of the 3.3 volts filter capacitor.

(I did the backup and flashing in two separate steps.)

Hey! so i flashed the chip and all well. But when i calibrate the power, it stays on 2.5watt even the attached appliance is 100% off? Did i do something wrong or is the onboard powermeter not very reliable? I did an athom plug the same way and no problems there...

Apart from the 2.5W issue, which seems similiar to the problem I read in this topic:
https://www.elektroda.com/rtvforum/topic4047633.html
do everything else works correctly? Are 100W, 200W, etc, loads correctly measured?

thank you for the quick reply. Ill have a new go at calibrating (although i did it the same way as the athom) and read the given topic.
once i know more ill report bank!

I had an old LSC smart plug without the energy monitor and with the strange labeled CB2S board (the one with the T cpu instead of the N version)
Anyway.... I flashed it using my DOIT ESP32 devkit V1. Or actualy only the CP2102 USB-serial chip which is on that board. The power supply on that board can power the ESP32 so it should be, and is, ably to power a CB2S board.

So i connected it as follows:
3V3 to 3V3
GND to GND
TX to TX *
RX to RX *
EN to GND **


* YES this is right. TX to TX and RX to RX.
The TX/RX lables on the ESP32 devboard are labled from the ESP perspective. So from the CP2102 perspective it is the other way around.
So the label TX on the board is the TX of the ESP and is connected to the RX of the CP2102

** This is the main trick in this method. EN is the "chip enable" pin of the ESP32.
Pulling EN to GND makes the ESP32 inactive. Effectivaly leaving you with just the CP2102 USB to serial converter and a powerfull enough 3V3 powersupply.




I bought myself a new LSC powerplug yesterday. It turns out to be the 3202087 from Action. Opened it with just two small screwdrivers and some plastic strips. The plug itself is made of soft plastic which makes it very forgiving with regard to eventual damage. I love them.