Sending works, receiving doesnt: MEGMEET power supply

[widdlle]

Hi there.

I have a problem and can't get any further on my own. I can switch the power supply unit on and off, but I don't get any read values. Does anyone have an idea what the problem is? Is it possible that I am using the wrong ID's as it is not an original Huawei but a MEGMEET power supply?

Many thanks in advance

I am using https://github.com/mjpalmowski/CAN-BUS-control-R4875G1-with-ESPHome-and-MQTT/releases/tag/v0.98
with GPIO 19 for tx and GPIO 21 for rx

[mjpalmowski]

Try this experimental OTA update you have to upload this file via the r49xx web-app, there is an OTA upload field at the bottom. Once it is uploaded it will forget your wifi and reboot, so you need to wait and connect to the r49xx hotspot and go to 192.168.4.1 again to connect it to your wifi. I have updated the request ID for the data sensors, see if this is any better.

[widdlle]

magnificent

reconnect and boom, valid values

Not all but enough to light up the test bulb.

What do you mean is it possible for you to fill in the missing values? Can I help you with this somehow?

[mjpalmowski]

Interesting that the amp values are not being displayed properly, I will have a look why that might be. It could be that the amp scaling factor is undefined. It's not going to be easy for me to figure out the scaling factor since I do not have a Megmeet, maybe someone in the community knows? Let's try 1024... and see if you get values. Can you give me a complete screenshot with Amps set to 10A please

[widdlle]

Sure here. Update was done before

[widdlle]

I tried something with an Arduino UNO and CANHacker, maybe i can help or try some frames

[mjpalmowski]

OK, here is another tweak I have now changed the set max amp sensor to divide by 1024. And I have set the voltage and amp settings to be updated every second, to keep the actual DC output Amp data flowing. One more thing, can you please give me the Log output after you hit "18 SETUP this Charger" button, it looks like it is detecting the Current capaility OK as 52A, that would make things really easy if that's true.

[widdlle]

hi after the new tweak

[mjpalmowski]

if you want to play with the CAN BUS tool that you have there. Have a look here for some relevant CAN hacking info. Also download the EXCEL file here

[mjpalmowski]

Ok the scaling factor is automatically detected, great. Now we have to figure out why you don't get any Amp readings. Does the Fan control work? How about input AC current, it shows zero, does it work?

[widdlle]

No if i change the value fan minimum speed the fans dont spin up and the AC Current always shows zero.
I tried 0x108040FE and get this

[widdlle]

Hi, can you please provide the yaml from the r48xx-off-grid.ota-MEGMEET3.bin?
I have to change the line 605 to - can_id: 0x1080407F and 628 to case 0x82: id(output_current_sensor).publish_state(value); break; in the canbus section to get valid DC Values.

Thank you in advance

[mjpalmowski]

Here is an OTA.BIN and here is the YAML. I did not change the can_id to 0x1080407F but kept it at 0x1081407F because the Megmeet doesn't respond to the "request to all" if queried at 0108140FE:

so you will need to change line 1767 as well to query 0x108040FE which gives valid responses on 0x1080407F as you show above.

But the 0x82 value makes sense, I have changed that for this OTA.BIN.

let us know how it goes:)