Modbus communication between Micrologix 1400 as Master and ABB softstarter as slave

[pravinshinde]

Hi all,
I am doing communication between Micrologix 1400 and ABB softstarter through modbus ,below I have mentioned details.
System:-
We have Micrologix 1400 with 1763-NC01 (Connected to channel0)to communicate with ABB softstarter
Protocol to be used :-ModbusRTU
Media :- RS-485
Following are the Settings done in SoftStarter
F055- Enable Communication
F056-19.2, Baud Rate
F057-01 ,Slave Address

Following are the settings made in Modscan (pc) to communicate with soft starter through the help of RS232-485 converter and it is communicating.
Baudrate:- 19200
Wordlength:-8
Parity-Even/Odd- It is working with both Parities and not working with Parity “NONE”
Stopbits-1
Cable connection used is straight ie:- D+ to D+,D- to D-,Sheild to shield
Also I have succeeded to make communication between PLC and PC with Modsim.So it is confirmed that both softstarter and PLC is working with pc

Problem:- PLC is not communicating with Soft starter,
cable connection details as BELOW:-
d+ connected to B in 176-nc01
d- connected A in 176-nc01
Sheild connected to COM in 176-nc01

Please find the Enclosed Rslogix500 file to see the configuration for channel0

 

[bernie_carlton]

The message block will attempt 1 message per off -> on transition of the enable line. Add another rung which tests if either en DN or the ER bits of the maessage are true then, if so, unlatch (OTU) the enable (EN) bit of the message.

You may with to try swapping the two communication leads. There is little agreement as to the appropriate polarity listing of the two communication wires in RS485.

 

[pravinshinde]

Dear Bernie,

Thanks for your reply.As per your suggestion,i have already tried this procedures but i did not get any results...

 

[pravinshinde]

Hi all,

Any suggestion for this issue ?

 

[Firejo]

The MicroLogix 1400 is an RS232 device (even when it’s a Modbus port). AB sells an adaptor (1763-NC01) designed to interface Micro’s with RS-485.

 

[rohitmane]

dear sir bernie_carlton
i want to transfer data from micrologix 1400 to compact logix l32E for this i have configure micrologix 1400 as modbus slave in channel configuration and also configure some of the tag to holding register .but i am not getting data to plc and also in laptop on modscan
please provide me how to configure micrologix 1400 as slave is there any pdf that can help me. similiar pdf which contain how to configure plc as master and slave in rs logix 5000

 

[widelto]

Dear Rohitmane: Why don´t you create a new thread. By the way, ML1400 has ethernet, L32E has ethernet then why modbus.?? Just use msg between them, there are a lot of examples here just look for them.