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Greg

Help!

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Hi to Modicon experts, Help me please with some issues, it's my first time working with momentum and concept. 1. i cannot connect to the CPU i'v tried trough the ethernet port and RS-485, it takes few second about 15-20 seconds to establish the connection and finally appear pop-up window and says "Timed-out waiting for response from controller" Error ID:OL9-1501. 2. how can i get information from slave devices connected to momentum ModBus via RS-485? 3. What the distance of MBP cable that connected between the two IO slot's should be? 4. if it's not difficult could you please make example configuration for the next items: CPU 171 CCC 98030, MBP 172 PNN 21022, ADI 350 00, ADO 350 00, or instruct me please. Thanks a lot in advance, Best Regards, Greg.

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Hi to all, in the end i fixed that problem, mad the connection through Ethernet with ethernet configurator. now i have another question: i have few(4) devices connected on modbus RS485 to my PLC, i have been told that i can read it's data with XXMIT function, but i didn't saw where i determine the slaves addresses, any help with this application if there are any other solutions or if you can instruct me with this one. Thanks in advance, Best Regards, Greg.

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If I remember well XMIT function has 16 registers the tenth register should be a "Pointer" in which you should define the first word (4x ) address (decimal value) of the Modbus Function call. For example if you have XMIT registers from 400100 to 400115 if you set 200 in 400109 it means that at address 400200 you'll find the first "object" of the modbus communucation string. The modbus string is composed of 5 registers: 400200: Number of function code (modbus) 400201: Number of data to read or write 400202: Slave address (1-247 ... 0 for ALL) 400203: First address slave data register (offset decimal value without 4x) 400204: First address master data register (offset decimal value without 4x) Please verify well what I said because probably I'm not exactly remembering this function

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Hi aggattapauer, Thanks for suggestion, i found explanation in Help about an array and it's parameters. but now when i connect through the RS-485(3-,8+) to the slave device i cannot read it's data, the "Active" bit always "on"-means that PLC working on modbus. popups Error message 116-"Modbus response message time-out". I did few checks: 1) Connected to PLC through Ethernet with modbus simulator(Master, Slave) all works. 2) Connected to PLC through Serial with modbus simulator(Master, Slave) no working no matter what i try to do. if it will help you for for Command variable i set Bit3=1(Bit 3 Enable RS485 mode Set to 1 when the selected port should operate in RS485 mode. Otherwise it defaults to 0, which is RS232 mode. When using port 2 of a Momentum PLC in RS485 mode with Modbus Messaging, make sure to use exactly the same parameters (baudrate, databits, stopbits, parity) for the XXMIT block as configured for that port.) and Bit8=1(Bit 8 Enable Modbus messaging Set to 1 when you want to send Modbus messages out of the PLC. Modbus messages may be in either RTU or ASCII formats. When data bits=8, XXMIT uses Modbus RTU format. When data bits=7, XXMIT uses Modbus ASCII format. Only use Bit 7 OR Bit 8, do not try to use both.) and parameters for Baudrate=9600, Databits=8, stopbit=1, Parity=none as it all configured in port2 configuration. I have been told and also i saw that for momentum PLC's RS485 pinout different not (3&8 pins) as i know it's programming cable, am i right? or what could it be? Any suggestions will be accepted with all respect guys it's very urgent i have to finish it in next days, anybody who can help i'll be very pleased and greatfull. I'll be keep trying to fix this up, if there will be any successes ill let you know. Thanks in advance, Best Regards, Greg.

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ok guys fixed this problem, by welding an 9-d connector 1,2 pins short and output probe, 6,7 pins short and output probe. in concept command equal to 8448 and MsgLen=5. and all works great! anyway thank you for reading and trying to help.

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