Modbus RS485 to USB communication

Industrial
42

maybe NODE-red has no access to your usb/com port where i believe your device is connected to, You mentioned usb-rs485 adapter connected direct to meter right, you proved that your connection is right with modscan, was such setup ever worked for you with diff device before? be sure that nothing ele is using this com port while you deploy node-red flow

43

Yes you are correct. I think i have issues with my node red. i will try uninstall install node red again

44

hi...

how about the progress? still not working? maybe i can share my modbus rtu node for your reference

45

image
image1366×768 89.5 KB

image
image1366×768 88.7 KB

46

Though i have uninstalled and installed i got no success :cold_sweat:

47

hi, maybe u can compare with my node setup as seen below

node-red-modbus version:

modbus-contrib-version
modbus-contrib-version709×364 8.98 KB

modbus-getter setup:

modbus-getter
modbus-getter918×543 20.7 KB

48

modbus-server setup:

modbus-setup
modbus-setup809×917 32.4 KB

nodered version:

nodered version
nodered version297×512 8.14 KB

49

nodejs version:
node-version

and with this flow json

[{"id":"582f1736.87a998","type":"modbus-getter","z":"77e78410.d9584c","name":"","showStatusActivities":true,"showErrors":true,"logIOActivities":false,"unitid":"40","dataType":"HoldingRegister","adr":"15019","quantity":"2","server":"d44638ff.6e6458","useIOFile":false,"ioFile":"","useIOForPayload":false,"x":900,"y":660,"wires":[["f1eb0b8f.50bd58"],["cfc300f2.8b8aa"]]},{"id":"e8c6b3cc.59875","type":"inject","z":"77e78410.d9584c","name":"30s","topic":"","payload":"","payloadType":"date","repeat":"","crontab":"","once":false,"onceDelay":"1","x":730,"y":660,"wires":[["582f1736.87a998"]]},{"id":"f1eb0b8f.50bd58","type":"debug","z":"77e78410.d9584c","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","x":1090,"y":640,"wires":[]},{"id":"cfc300f2.8b8aa","type":"debug","z":"77e78410.d9584c","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","x":1090,"y":680,"wires":[]},{"id":"d44638ff.6e6458","type":"modbus-client","z":"","name":"USB1","clienttype":"serial","bufferCommands":true,"stateLogEnabled":false,"tcpHost":"127.0.0.1","tcpPort":"502","tcpType":"DEFAULT","serialPort":"/dev/ttyUSB1","serialType":"RTU-BUFFERD","serialBaudrate":"19200","serialDatabits":"8","serialStopbits":"1","serialParity":"even","serialConnectionDelay":"5","unit_id":"","commandDelay":200,"clientTimeout":300,"reconnectTimeout":5}]
50

Dear Friend,

In your case you are using USB port to take external device to node red. But in my case it shows as COM13 . I have uploaded all related data above in the chat for your reference.

image
image827×632 48.5 KB

51

this is what i got with your program. Its sure there is some thing that doesnt allow me to open the com port and do this job. Can i take any advice from any node red support guy. Do you have any contact of such a guy?

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image1091×539 24 KB

52

can you try to read full block of registers not just 1 or 2 from i.e. power table but all ?