Micrologix 1000 PLC to PC data acquisition problem! please help!

Sir, Could you please help me? I need to pull up temperature values from RS linx to Micrologix 1000 PLC using modbus. I've been trying for days now and i havent succeeded yet. I need help, Sir

I am using 1420 Emerson Smart gateway and 648 temperature transmitter connected to 3 wire RTD to get the temperature values. now i somehow need to get the values to the PLC using modbus, I've even checked the baud rate, parity for the gateway and PLC but it hasnt been of much use. I'm nearing the deadline for my submission. Please. Help me.

Thank You and Regards
Ashish

Your ML1000 does not support modbus protocol. Do you already have the ML1000?

Modbus

yes it supports Modbus. What other options do i have? is there any other way/ protocol i could use? please help

i have a micrologix 1000 and 1200 at my lab

A ML1000 supports DF1 or DH485 protocol. There is a analog ML1000.
What is the complete catalog number of your ML1000?

Or upgrade to a ML1100,1200 , 1400 or 1500 they support modbus protocol.

rokaboi said:

i have a micrologix 1000 and 1200 at my lab

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See pdf below for some help on setting up your ML1200 for modbus. Does your ML1200 have one comm port or 2?

It has One com port Sir,

I have Micrologix version 5.50 i need version 6 for the Modbus RTU Master Driver. What do i do Mickey?

rokaboi said:

It has One com port Sir,

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FYI, once the comm port is configured for modbus protocol you will not be able to communicate with it using RsLinx's DF1 or DH485 protocol for monitoring or programming your processor.
See pdf below for a work around this using the communication toggle push button.

rokaboi said:

I have Micrologix version 5.50 i need version 6 for the Modbus RTU Master Driver. What do i do Mickey?

Click to expand...

Call your local Allen Bradley representative. Or upgrade to a ML1100 the software for that is free.

Ashish, you need to clarify your question. I do not understand if you need to get data from the Rosemount 1420 into the MicroLogix, or into RSLinx, or into some other application.

For those of you playing along at home, the Rosemount 1420 is a wireless instrumentation gateway. The Rosemount 648 is a temperature transmitter that communicates with the 1420 Gateway via a proprietary "self-organizing" radio network.

The Rosemount 1420 can be a Modbus RTU Slave, or a Modbus/TCP Server, or even an OPC Server itself.

To get data from the Rosemount 1420 into an Allen-Bradley control system, the MicroLogix 1100 controller would be ideal because it has an RS-485 2-wire port (use the 1763-NC01 cable) that supports Modbus RTU Master or Modbus RTU Slave, and also has an Ethernet port.

Also, the RSLogix 500 "Micro Starter Lite" edition is free of charge. The current RSLogix 500 software that Ashish has is about five years out of date and will not support modern MicroLogix controllers and operating systems.

In order to use the existing hardware, three things are necessary:

1. Upgrade RSLogix 500 software to the current revision.
2. Upgrade the MicroLogix 1200 operating system to the current revision.
3. Install an RS-232/RS485 converter between the MicroLogix 1200 and the Rosemount 1420.

If you did all of those things, you would be able to write logic in the MicroLogix 1200 controller to read data from the Rosemount 1420, which in turn would have the temperature values from the Rosemount 648 temperature transmitter.

However, the data would be "stuck" inside the MicroLogix, as there is no second serial or other network port to access the controller. Unless the MicroLogix is the end-point of the system, I don't see how that helps.