CQM1H-SCB41 TO 3G3MV

[Yair 2]

Hi every one, Have a project with 6 inverters 3G3MV connected to CQM1H-SCB41 RS485. This is the CX-protocol file see line_2_v3. The communication working fine. My problem is, If one of the inverters is disconnect from the network or not connected to the power supply the plc doesn't keep increment the internal counter N in order to communication with the other inverters. for example number 02 is disconnect now see trace11 I know that I can write the protocol for each inverter with constant address to solve this problem but I prefer working with the internal counter because it is more easy to add inverters. Thanks,

[Yair 2]

trace11

[Jay Anthony 118]

Handling Missing Nodes in a Multi-Drop Protocol @ MrPLC.com

[Yair 2]

Thanks for the information Jay

[Yair 2]

This is the cx protocol file with handling the missing nodes. Up to three nods can be missing. Thanks you Jay, now the communication working fine. BTW If number 5 is missing and 6 isn't then there are unnecessary tow step that trying to communicate with number 7 and 8 (they are not exist in the network).

[Yair 2]

I just finish running the B&B line_2 project This the cx_protocol file for 16 inverters I didn't find the way, how to us the Internal counter N for address 10-16 --> A,B,C,D,E,F,10 Is it possible to us it ?

[Jay Anthony 118]

There is no hex math available in CX Protocol. Can you change your inverter unit numbers to 16,17,18,19,20,21?

[Yair 2]

Thanks Jay, I thought about this solution, but in the future They may add more inverters to this line. So I prefer to keep the inverter numbers from 1- to 16 Any way thanks for help.

[Irvly 0]

Hi Yair,

are you mind to share you program for this to me, i have similar project that using 2 inverter 3G3MV with CPU CQM1H. this project, already old project but i need to replace the screen in beginning but somehow the inverter giving alarm CAL and i not so understand where the logic for communication. I hope with looking you case can find solution in here.

really appreciate if you can share it.

Thanks & regards,

Irvan  

[Michael Walsh 268]

@Irvly This thread is 16 years old.  I have tagged @Yair to give you a better chance of getting a response.