Thanks for this informative video. Have you checked the accuracy of the temperature readings from this sensor? I plan to use these for my home automation project, but there are a few comments online stating that temperature reading is too high (probably because the sensor chip heats up from the circuitry).
Hi Csongor Varga, i have a problem with the 485 configuration software when i choose the port and send click i dont have a correct answer but the connection is fine because i can see the sensor with modbus scan, i need the 485 software to change ID.
Szia, van olyan progid amivel lehet konfigurálni a szenzort? értem ez alatt a device id cserét, mert ugye alapbol mindé 1... és ha több dolgot is akarsz egy rtu-ra akasztani... milyen progival lehet ezeket meg akár más modbus eszközt állítani? plc-re aggatnék tanulás céljából egy másik ehhez hasonló, csak dobozolása más, meg egy pzem-016 meg majd egy relé board-ot... de device id-t ugye állítani kell... a másik kérdésem parám hogy alin mindenhol 9600-as baud-ot irtak azzal is próbáltam sikertelen... akkor ezek szerint a 4800 a nyerő ezeknél? viccesek a kínaiak ...
I'm working on a project using the same sensor using the modbus communication method, but I'm having a problem if the temperature condition is negative then the displayed number doesn't match (eg temperature -20.XX°C the number shown is 6541.7. Any solution for this problem?
Yes, this is how normally the negative numbers are represented. If the top bit is on, the number is a negative number. So if the raw value is >32768 than the number is -1 * x - 32768.
Hello sir, thanks for your tutorial, I've purchased that sensor and downloaded the CAS MODBUS SCANNER, it does detect the device but it send and error instead of the readings, do you think my device is faulty?
Can you give a bit more explanations about the code that you mention in 19:00? I'm trying to understand what happened there but no result yet :) Any resource link would be nice.
It is only about converting the data from the sensor. You need to read 2 registers form the device over modbus, which is 4 bytes. The lower two bytes gives the humidity and the last two bytes the temperature. In each byte pair the first byte is the last 8 bits of the 16bit integer number, and the second byte is the lower 8 bits. And the code just puts the two back together. Nothing more. And yes the value being returned is 10 times the actual value, so I am diving it by 10. So it is just simple calculation, nothing special.
I have 3 temperature/humidity sensors that I would like to connect to the modbus. I need to change the RTU numbers to make the numbers unique. Where can I obtain the 485 parameter configuration tool control.exe you show at time 6:25 (6:25 / 20:25) in the video?
Oh sorry, Google considered this file suspicious and this is why it was not available for you. I requested a review from Google. I can email it to you if you drop me a mail (csongor dot varga at gmail dot com)
Hi, I have the XY-MD02 device, I gave voltage:15 V, using simply modbus master I am try to read function code 3 but it didnt give any response so what was the mistake ? please help me how to start with this .
Hi Congor, congratulations. Nice video. I´m trying to learn modbus with Node Red. I have a problem in Node Red, the problem is "Error: {"name":"PortNotOpenError","message":"Port Not Open","errno":"ECONNREFUSED"}" Could you help me? I putted the same node. Thanks
Are you sure you have provided the correct port? In your setup you may have a different name for the USB port. I think you can check your USB device using udev in the console.
We got this from here, and yes they work with a PLC or HMI: www.aliexpress.com/item/Temperature-and-humidity-transmitter-rs485-modbus-temperature-sensor/32400484544.html?spm=a2g0s.9042311.0.0.1eNJ8W
Olá, por favor vê se consegue me ajudar, comprei 7 sensores deste, preciso colocar todos numa mesma rede modbus RTU, mas não consigo usar o software que você mostra acima para download, meu supervisório scada lê eles normalmente, porém todos estão com o endereço 1 e não consigo alterar o endereço, já teve sucesso com isto.
Hi, I have this same problem? Have you solved it? I want to connect 8 of these sensors to a modbus/scada gateway for temperature control. Thank you for your help.
Actually, this is good question. My sensor is inside so it has not measures negative values yet. I might have overlook this, but for now I have no way of testing. I don't have a connection to the manufacturer to test.
@@darktricks5970 There are hunderds of different plc-s on the market, each have dozens of different variants. How do you expect me to give a guide to your particular model.
Oh sorry, Google considered this file suspicious and this is why it was not available for you. I requested a review from Google. I can email it to you if you drop me a mail (csongor dot varga at gmail dot com)
That is a good question. Arduino has a serial port, so you should be able to get a RS232 to RS485 converter. If you google "arduino modbus" you can see some examples. This is not something I ever tried.
Actually i wants to set this temperature and humidity sensor with Arduino and via RS485 shield i want to send data to my machine. In this case Arduino will be modbus slave and Laptop will be my master. could you suggest me some links ?
