Control.com - Nerds in Control

I'm new to the PLC game and wanted to know if anyone has successfully programmed a Micrologix 1100 to interact with a Telemecanique motor starter that has a modbus module (LUCB12BL). An example file or steps showing how to configure the serial channel in RSLogix500 would be greatly appreciated.

I have the PLC and motor starter wired using the RS485 wiring schematic for modbus. Im using the 1763-NC01 cable to connect the 3 wires required for modbus to the PLC.

Also, im a bit confused as to the master/slave terminology. Is my PLC the master and the motor starter the slave? My application is simply to monitor the status of the motor starter and report any errors to an HMI connected to the PLC.

cheers
aditya(at)eascan.com

I'm pretty sure you are going to need sycon software to config the tesys starter for communications. As there is no fixed words for every condition. You have to select in sycon what you want to read and assign that to certain words.

The Sycon software is not required since the TeSysU is using a Modbus connection. Contact your local Schneider Electric office or go to www.schneider-electric.com to locate the manual on the particular TeSysU starter and communication adapter that you have. The manual will provide you with the particular Modbus registers that you are looking for.

I've read the entire manual for the LULC031(the modbus module in the TeSysU starter) and i'm trying to setup a basic ladder logic program in RSLogix500.

In the manual it says there is a 16-bit register, 457, that has bits that change when the rotary handle on the starter is On or Tripped. I thought i would use this mechanical input and display their states on the LCD of the 1100 processor.

I only have 2 rungs in my code - one for the LCD and one for the MSG. I have setup the Message such that it uses Channel0 (setup for Modbus Master) and following settings:

* Modbus Command: 03 Read Holding Registers (4xxxx)
* Data Table Address: B3:0
* Size in Elements: 1
* Data: 16 bit

* Message Timeout: 2 (seconds)
* MB Data Address: 457
* Slave Node Address : 1
* Modbus Address : 40458 (this field is automatic based on "MB Data Address")

Am I correct in understanding that by specifying B3:0 and the data to 16 bit, when the data returns it will populate B3:0/0 to B3:0/15?

I am unsure of the MB Data Address field. The modbus addressing of 400001 to 49999 versus the register number 457 is confusing me.

Does anyone see whats wrong this configuration? I keep getting Error Code 37 (hex) - Message timed out in local processor.

Also, on the TeSys starter, I have the COMM and ERR lights flashing alternately. According to the manual this means "Bus parameters are being initialized"

Thanks.

...figured it out. Two problems were found:

1) Incorrect wiring. I was using a CAT5 cable, RJ45 on the TeSysU end and the 1763-NC01 adapter on the ML1100 end. The wiring should be as follows:

1763-NC01 PIN B = RJ45 PIN 5 => D0
1763-NC01 PIN A = RJ45 PIN 4 => D1
1763-NC01 PIN COM = RJ45 PIN 8 => COM

2) Incorrect addressing. When setting up the MSG block in RSLogix500, the "MB Data Address (1-65536)" field needs to be 1+RegValue in the TeSysU. (that is, to access reg 457, enter 458).

A helpful article for configuration from the AB knowledgebase: " "Quick Start" Communicating ModBus from a MicroLogix 1100 to a PowerFlex 4/40 drive and EtherNet to a PanelView Plus.
") - or Answer ID 33774