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[BK7231N][CB2S][CSE7759B] Tuya WiFi Energy Meter EARU EAWEM-T-CT

taktlos 7743 48
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  • Helpful post
    #1 20840240
    taktlos
    Level 11  

    Not so lucky (this time) a purchase from Aliexpress

    What we receive in the shipment. Module already disassembled, but without major problems because only 6 rivets needed to be removed.
    Components of the EAWEM-T-CT energy meter purchased on Aliexpress.



    More parts:
    Photo of a disassembled white electronic device with visible interior and wires on a colorful background.



    Chipsea - Electric Energy Measuring Chip
    Close-up of an electronic circuit board with various components.

    Datasheet of CSE7759B


    Close-up of an electronic module featuring a Chipsea CSE7759B chip.



    CB2S:
    The image shows a disassembled electronic module purchased from Aliexpress, lying on a checkered fabric. Several screws and components are visible in the background.



    CB2S electronic module on a green PCB



    For the moment, I've stopped here
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  • #2 20842631
    p.kaczmarek2
    Moderator Smart Home
    Hello, have you tried to take a 2MB flash read from this chip? It may work with OBK, we will see. I can guide you step by step through the process.
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  • #3 20843524
    taktlos
    Level 11  

    It would be great because up until now I have failed miserably when trying to read the firmware. I've found the way to power up the board but I'm having problems with TX and RX due to lack of experience.
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  • #4 20843636
    p.kaczmarek2
    Moderator Smart Home
    Isn't RX/TX used here for communication with CSE7759B? Maybe you need to temporary cut the connection.
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  • #5 20843646
    taktlos
    Level 11  

    I was trying to connect directly to CSE but without any luck.

    [Edit]
    And where should I cut if that is a solution for backup fw? I can remove CSE for the time being but I'm not so sure that I will be able to place it back due to my soldering skill. ;)
  • #6 20843667
    p.kaczmarek2
    Moderator Smart Home
    Wouldn't it be easier to desolder the white ribbon cable?
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  • #7 20843676
    taktlos
    Level 11  

    The ribbon itself has already fallen off, probably due to its quality. :)

    I will give it another try in the morning because my iron is already in a locker. Thanks for your help.
  • #8 20843806
    p.kaczmarek2
    Moderator Smart Home
    CSE7759B may interfere with the flashing of WiFi module. Once the connection to CSE7759B is temporarily removed, you can first make a 2MB backup of the flash, maybe extract Tuya Config from that, if possible, and later try to flash the OBK
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  • #9 20843847
    taktlos
    Level 11  

    No luck. Maybe I'm hooking up in the wrong places with RX and TX. Can you give me a hand with that?
  • #10 20843874
    p.kaczmarek2
    Moderator Smart Home
    So, where do you connect them currently? Which two of four pins on the white ribbon are VDD and GND? The RX/TX port of CB2S is at the PCB side, so it may be hard to follow it.
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  • #11 20843879
    taktlos
    Level 11  

    I'm connecting to CSE TX/RX currently. On the ribbon GND is on the 4th wire ---> oooם
  • #12 20843884
    p.kaczmarek2
    Moderator Smart Home
    Wait a moment. I was sure that CSE is on the other board. Are they on the same board? CB2S and CSE?

    As I said, it may not flash as long as CSE is here... can you show your connections?

    Can you watch this video, this will show you how we handle situation when there is a SOIC chip on flash line:



    Look at 2:25 time mark
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  • #13 20843887
    taktlos
    Level 11  
    On the other board there are only leds, resistors and one switch.
    Same board different faces:
    Close-up of a circuit board with various electronic components.
    Close-up of a PCB with an electronic module and red wires.

    and I'm hooking up to 8th and 6th pin of CSE.



    [EDIT]

    I managed to backup original FW and upload OpenBeken FW.

    I'm having now problems with reading iex. current vaules:
    Screenshot displaying data from the measurement device Earu_Eawem_T_Ct_1.




    This is what I've got from logs:
    [syntax=bash]Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8F 00 3B 10 01 25 0A 4C CC 28 03 9C 81 71 59 60 B1 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8F 00 3B 10 01 29 EF 4C CC 28 03 C8 BF 71 59 64 08 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 92 00 3B 10 01 29 EF 4C CC 28 03 D3 44 71 59 67 9E 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 92 00 3B 10 01 14 F1 4C CC 28 04 2E E0 71 59 6C 88 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 91 00 3B 10 01 14 F1 4C CC 28 04 2E E0 71 59 70 8B 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 91 00 3B 10 01 14 F1 4C CC 28 04 6A B1 71 59 74 9C 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 91 00 3B 10 01 3F 5B 4C CC 28 04 51 30 71 59 77 9A 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 3F 5B 4C CC 28 04 20 DE 71 59 7B 1A 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 3F 5B 4C CC 28 04 20 DE 71 59 80 1F 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 10 9C 4C CC 28 03 73 94 71 59 85 3E 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 10 9C 4C CC 28 03 95 3C 71 59 88 0B 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 31 34 4C CC 28 04 1F 1B 71 59 8C 32 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 91 00 3B 10 01 31 34 4C CC 28 03 B3 11 71 59 90 C0 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 91 00 3B 10 01 31 34 4C CC 55 5A 02 BE 58 00 05 91 
    Info:EnergyMeter:Skipping packet with bad checksum 43 wanted 91
    Info:EnergyMeter:Consumed 16 unwanted non-header byte in CSE7766 buffer
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8F 00 3B 10 01 3E 4E 4C CC 28 04 07 B3 71 59 98 E4 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 55 5A 02 BE 58 00 05 8F 00 3B 10 01 25 C7 4C CC 28 
    Info:EnergyMeter:Skipping packet with bad checksum C8 wanted 28
    Info:EnergyMeter:Consumed 7 unwanted non-header byte in CSE7766 buffer
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 55 5A 02 BE 58 00 05 90 00 3B 10 01 25 C7 4C CC 28 
    Info:EnergyMeter:Skipping packet with bad checksum C9 wanted 28
    Info:EnergyMeter:Consumed 7 unwanted non-header byte in CSE7766 buffer
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 3D 56 4C CC 28 03 5C D6 71 59 A4 6F 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 92 00 3B 10 01 3D 56 4C CC 28 04 51 82 71 59 A8 17 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 92 00 3B 10 01 2C DD 4C CC 28 04 3F 59 71 59 AC 56 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 2C DD 4C CC 28 03 FD AD 71 59 AF 68 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 55 DF 4C CC 28 04 3E 98 71 59 B3 C4 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8E 00 3B 10 01 55 DF 4C CC 28 04 93 FD 71 59 B6 7F 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8E 00 3B 10 01 4A 20 4C CC 28 03 FE 5F 71 59 BA 85 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 4A 20 4C CC 28 03 FE 5F 71 59 BD 8A 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 4A 20 4C CC 28 04 37 1A 71 59 C1 83 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 3A F4 4C CC 28 04 14 47 71 59 C4 54 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 3A F4 4C CC 28 04 04 5E 71 59 C8 5F 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 27 0F 4C CC 28 04 54 2F 71 59 CC 8C 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8E 00 3B 10 01 27 0F 4C CC 28 04 40 32 71 59 D0 7D 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8E 00 3B 10 01 23 41 4C CC 28 04 40 32 71 59 D3 AE 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8E 00 3B 10 01 23 41 4C CC 28 04 34 E3 71 59 D7 57 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8E 00 3B 10 00 FF F1 4C CC 28 04 34 E3 71 59 DB E6 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8D 00 3B 10 00 FF F1 4C CC 28 04 57 7B 71 59 DF A4 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8D 00 3B 10 01 2E 5D 4C CC 28 04 57 7B 71 59 E3 44 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8D 00 3B 10 01 2E 5D 4C CC 55 5A 02 BE 58 00 05 8E 
    Info:EnergyMeter:Skipping packet with bad checksum 65 wanted 8E
    Info:EnergyMeter:Consumed 16 unwanted non-header byte in CSE7766 buffer
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 8E 00 3B 10 01 31 6F 4C CC 28 04 0B B0 71 59 EA 4A 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 55 5A 02 BE 58 00 05 8E 00 3B 10 01 31 6F 4C CC 28 
    Info:EnergyMeter:Skipping packet with bad checksum 7B wanted 28
    Info:EnergyMeter:Consumed 7 unwanted non-header byte in CSE7766 buffer
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 55 5A 02 BE 58 00 05 8E 00 3B 10 01 1B FA 4C CC 28 
    Info:EnergyMeter:Skipping packet with bad checksum F0 wanted 28
    Info:EnergyMeter:Consumed 7 unwanted non-header byte in CSE7766 buffer
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 1B FA 4C CC 28 03 49 40 71 59 F7 9B 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 3A 15 4C CC 28 03 F2 35 71 59 FA 76 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 3A 15 4C CC 28 04 4F 4C 71 59 FE EF 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 46 A9 4C CC 28 04 93 FB 71 5A 01 86 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 46 A9 4C CC 28 04 2C 3B 71 5A 05 63 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 46 A9 4C CC 28 04 2C 3B 71 5A 09 67 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 46 A9 4C CC 28 03 7E EC 71 5A 0E 6E 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 24 59 4C CC 28 03 97 C5 71 5A 12 F2 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 24 59 4C CC 28 04 06 DA 71 5A 16 7B 
    Info:EnergyMeter:CSE7766 received: 55 5A 02 BE 58 00 05 90 00 3B 10 01 24 59 4C CC 28 03 9E A1 71 5A 1A DD 
    [/syntax]


    Any chances to get current values?

    When I sent GetReadings command I got in return:
    Code: Bash
    Log in, to see the code
  • #14 20852220
    p.kaczmarek2
    Moderator Smart Home
    Have you tried calibrating your device? Commands are the same as in Tasmota, VoltageSet, etc
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  • #15 20852678
    taktlos
    Level 11  

    Yes. Couple of times with different loads but with the same output = NaN
  • #16 20852687
    p.kaczmarek2
    Moderator Smart Home
    Are you sure that CSE7759B and CSE7766 are using the same protocol? I don't remember checking my driver on CSE7759B, you may be the first one with it.
    I may need to adjust the driver if there is a difference

    Is only current read broken, voltage and power are correct?
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  • #17 20852745
    taktlos
    Level 11  

    Nothing has changed since my post #13. I'm after this current reading. Calibration is done and fine.

    Let me know what additional info or logs from my side you require.

    [Edit]
    This is what I got:
    Screen showing data from EAWEM_T_T_CT_2 device reading with information on voltage, power, and energy consumption statistics.


    As per my research, Tasmota uses the same driver for both CSE.
  • #18 20914579
    Ciberyan
    Level 1  

    Hello!
    Any chance to see progress on this one?
    I would be very interested as well.
    Thanks in advance.
  • #19 21007540
    cyber5
    Level 5  

    >>20843887

    Hi taktlos, reading the volts, amps and watts from the serial data of the CES7766 (or CSE7759) is explained here:

    Link

    Make sure the serial link is set to 4800bps. Each meter reading (from the CSE chip) is 24 bytes. The code below assumes you have read the 24 bytes from the CSE chip into inData[] (byte array) (starting with 55 5A) .

    Extract the volts from the inData byte array like this:

    ULONG voltage_coef = GetData(inData[2], inData[3], inData[4]);
    ULONG voltage_cycle = GetData(inData[5], inData[6], inData[7]);
    float voltage = (float)voltage_coef / (float)voltage_cycle;


    ULONG GetData(byte h, byte m, byte l){
    return ((ULONG)(h) << 16) | ((ULONG)(m) << 8) | l;
    }

    Extracting the watts & amps is the same except use a different position in the inData array (as the instructables link above shows).

    Hope this helps. I find these CSE chips are sensitive and very accurate but they don't tell you the direction of the current.

    BTY, a NAN float value is probably caused by a division by zero. The most common mistake is shifting the data left in a byte and making it zero. The ULONG (unsigned long) data conversion in the GetData() function prevents this.
  • #20 21007547
    p.kaczmarek2
    Moderator Smart Home
    Thanks for you message. Any help with CSE is welcome. I don't have CSE at hand to check, but here is our current code:
    https://github.com/openshwprojects/OpenBK7231T_App/blob/main/src/driver/drv_cse7766.c
    We seem to do something similiar:
    Fragment of C code related to UART data.
    And here is the division:
    C code in a text editor with functions related to voltage, current, and power.
    So we should change type to ulong?
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  • #21 21007588
    cyber5
    Level 5  
    >>21007540

    One more thing. I have found not every reading from the CSE chip is good. The last byte is a checksum. Here is how to calculate it.

    byte calCkSum(){
      byte sum=0;  
      for(int i=2; i<23; i++)
        sum += inData[i];
      return sum;
    }
    


    I understand the coefficients in the data stay the same. So, you can test them too if you want.

    Added after 6 [minutes]:

    >>21007547

    "So we should change type to ulong?"

    Yes, or just do the type conversion to ULONG before the shift operation, like I show in my GetData() function.

    #define ULONG (unsigned long) 
    . . . 
    ULONG GData(byte h, byte m, byte l){
        return ((ULONG)(h) << 16) | ((ULONG)(m) << 8) | l;
    }
  • #22 21010697
    cyber5
    Level 5  

    Looking at the photos of the Tuya WiFi Energy Meter in taktlos's original post, the circuit does not appear to have the live AC side isolated from the DC side. If you try to flash that with it connected to the power it could destroy your computer. This also makes it hard to debug and the circuit could be dangerous to touch. So, maybe it is better to use a power meter that is properly built?

    Most cheap power meters from China have the CSE7759 chip in them which we know is easy to read with an arduino. The meter shown below came with an inverter I bought from AliExpress. I expect most cheap meters with an LED display from AliExpress are similar.

    The bottom photo shows the meter main PCB with the display PCB removed. I have connected the CSE7759 chip and 5V power to the Arduino pro-mini and been able to read the power meter with the code I described in my posts above. The meter still works and displays the watts and volts on the display board if you fit it to the main board.

    Looking at the main PCB (bottom photo), positioned at the bottom left is the 5V power supply module. Position at the mid-right on the main PCB is the ZMPT107 transformer which acts as an isolation transformer for reading the voltage. The CT current sensor is plugged into the top right connector. This totally isolates the DC side from the AC side and makes the DC side safe to work on and debug with the meter functioning.

    The bottom connector is for power. Above the ZMPT107 is the CSE7759 chip which is easy to connect to the arduino with just 2 wires.

    Another reason why this solution may be better is because many places (like Australia) have the home power meter in a metal meter box on the side of the house. So the WiFi won't work if it is in a grounded metal box. So, this way we can have the arduino+wifi+antenna mounted in a separate case on top of the meter box and connected to the power meter with a 3 or 4 wires. A proper antenna would also provide more wifi range. You might need to check that the arduino and wifi module does not overload the 5V power supply module on the main meter PCB.

    Digital AC power meter with LED display.

    Image shows the main PCB of an energy meter with CSE7759 and Arduino.
  • #23 21012775
    p.kaczmarek2
    Moderator Smart Home
    You are right, those devices are not isolated. I think that @DeDaMrAz already had issue related to that.

    Ok, so I've added your suggestion, can you check?
    https://github.com/openshwprojects/OpenBK7231...mmit/1d60854ea9cc43dcbaa2d91bbc23d0d710501773
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  • #24 21012832
    cdtdsilva
    Level 10  

    Will this read negative power? It seems most Tuya devices are configured from the factory not to, even when having a supported power meter IC such as the BL0942
  • #25 21013413
    cyber5
    Level 5  

    "Will this read negative power?"

    No, that's a big deficiency with the CSE7759 chip. Apparently, China hasn't learned how to read the direction of AC power yet. The only power meters I can find from China that read import/export power do it with two current sensors. Here is one from Tuya, but it is one of those non-isolated meters, so be careful. If you clip one CT sensor onto the AC output from the solar inverter and the other one onto the home mains, the difference should be the import/export power.

    Diagram showing the connection of a Chinese power meter with connectors and two current sensors.

    Link

    Alternatively, one way to read AC power and direction with an Arduino and one CT sensor is to use the Emon lib. See here: Link

    To do this you will have to construct the CT sensor and Voltage sensor circuits given in the schematic. Link

    That's not too hard. The website explains the calibration procedure. Link

    I am considering building a phase detector circuit for the CSE7759 chip which will indicate the direction of the current. I will post it here if I make progress on that.

    BTY, this is the meter in my post above. Apparently, it is the only one I can find with an isolated DC circuit. Just search AliExpress for: "Current Limiter Sensor for Soyosource GTN" Link

    Jesodim current limiter kit for photovoltaic grid systems

    If you want to read this meter directly from its RS485 port, there is code for that available. This code simulates the meter's RS485 serial output and explains the protocol. Link
  • #26 21013512
    cdtdsilva
    Level 10  

    Thanks for sharing. I wasn't aware of that sensor, using the two halls. That explains right the home assistant configuration with the strange two sensor input and 'calculations'.

    Meters based on the BL0942 can measure bi-directional. The problem is that the Chinese don't implement this feature on their firmware (it needs flashing with open Becken) and it's not always easy to know which ones have this chip.
    While they are not isolated, it is easy to isolate the BL0942 chip using a Silicon labs SI8621 or other equivalent, right at the serial interface, if the MQQT readings method is not suitable.

    PS: Calibration (and drift) from a hall sensor are a nonsense. With a standard shunt resistor, calibration is done once and fairly accurate throughout the load range. Super easy to do on OpenBecken too. Just connect a resistive load of known consumption and set the values on the web interface.

    I started a thread about it here: Link, so as not to hijack this one :)
  • #27 21014312
    cyber5
    Level 5  

    Hi cdtdsilva, thanks for that.

    Hey, would you like to work with me to build a nice bidirectional power meter module out of the BL0942 chip?

    Datasheet: Link

    Main parts:

    Components of the power meter module with chip BL0942: ZMPT101B voltage sensor, AC current transformer sensor, BL0942 energy metering chip, and power supply module.
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  • #28 21014387
    p.kaczmarek2
    Moderator Smart Home
    @cyber5 I can help with code if you need anything.
    The related topic is here: Meters capable of measuring negative AC power flow (For Solar) - and how to integrate with HA.
    basically, you need a flag in OBK to enable negative current, etc.

    Still, I haven't tested that, so if you find any problem, let me know!
    Helpful post? Buy me a coffee.
  • #29 21015381
    cyber5
    Level 5  

    Hi p.kaczmarek2, your help is more than welcome. Same with anyone else.

    A safe bidirectional power meter module for arduino is desperately needed. The wifi in those cheap non-isolated wifi meters from China won't work inside a metal meter-box because it is inside a Faraday cage. If someone tries fit an external antenna to the wifi module it could cause a big problem. This is because the ground (0V) in those non-isolated meters is connected directly to the AC neutral (N) wire. So if you use a coax cable to put an external antenna on top of your meter-box and use the meter-box as the ground plane, this will trip the earth leakage detector in the AC power circuit breaker. This is because some of the AC power going into the meter will return via the meter box earth (E) and not the neutral wire (N). The other problem is with trying to code, debug and calibrate a live circuit.

    The circuit below is based on the isolated CSE7759 power meter in my posts above. Both the CSE7759 and BL0942 chips use a 0.001 ohm shunt resistor for the amps and a 1000:1 divider circuit to measure the volts, so this should work. We could make the burden resistors variable for calibration?

    I have ordered all the components and will try to get a prototype working. Any suggestions are welcome. If, you want to start a new thread for this project that's ok with me.

    Power meter module diagram for Arduino with voltage and current sensors.
  • #30 21015462
    cdtdsilva
    Level 10  

    Hi cyber5,

    If you want to use the BL0942 as above, then my suggestion is to keep the mains referenced stuff and isolate at the RS232 level.
    I attach one such reference design for you to have a look - But in practice you can use any design and just add the opto-isolators to the serial line. You'll probably want to keep the WiFi chip on reset and instead use one externally, if WiFi range is a problem.

    I had a look at the CSE7759, but it doesn't appear to have a feature to measure the direction of the power flow. So you can't use that for a bidirectional power meter. It will give you the absolute value, but not the direction. It seems similar to the BL0937.

Topic summary

The discussion revolves around the challenges faced while programming the EARU EAWEM-T-CT power meter, which utilizes the CSE7759B chip. Users share experiences regarding firmware reading, UART communication issues, and the need for proper connections to successfully flash the device with OpenBeken firmware. Several users suggest methods for connecting the CSE7759B and CB2S chips, including desoldering components and using specific programming adapters. The conversation also touches on the differences between the CSE7759B and CSE7766 chips, calibration issues, and the importance of isolating the device during programming to prevent damage. Additionally, there are discussions about the limitations of the CSE7759B in measuring bidirectional power and the potential need for a new driver to support it.
Summary generated by the language model.
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