Posted 3 Mar 2015 I'm designing a PLC system in which a Micrologix 1400 talks Modbus TCP/IP with three Modbus TCP-capable SCR controllers. I've never done Ethernet/Modbus TCP communication using the 1400, so I'm asking the following questions: 1. Can I connect the 1400 PLC and the three devices to an Ethernet switch and configure Modbus TCP communication from the devices to the PLC (data collection only) ? The switch will also be connected to the customer's DCS, receiving the data from the PLC and the three devices. 2. Can I connect the Ethernet port on the1400 PLC to the Ethernet switch directly, or do I need some kind of Ethernet interface, like the 1761-NET-ENI ? 3. The system also includes an HMI, connected to the 1400 PLC by RS-232 communication. Any issues with communicating with the HMI and doing Modbus at the same time? Your help in this matter would be highly appreciated. Thanks. Ron Share this post Link to post Share on other sites
Posted 4 Mar 2015 I can give you some very quick sketchy answers that others will hopefully verify (or correct!). I haven't actually done an application like yours, but I've done a little research on it for proposed projects that never happened. 1) Yes, you should be able to do this. Modbus TCP can navigate standard switches. 2) The ML1400 Ethernet port can be used directly, no need for an interface. 3) The ML1400 can handle both Modbus TCP and Ethernet/IP at the same time, so the only potential conflict is the amount of data. HMIs use a lot of connections. You only have three other devices and the DCS, so you're probably ok there. Share this post Link to post Share on other sites
Posted 29 Apr 2015 (edited) Hi Raduvalas, I guess, there should be ethernet to modbus TCP protocol conversion. I am not sure if your PLC can make this conversion, however, you can also consider using a Ethernet to Modbus TCP converter which GW-7473 is an ICP DAS USA product. http://www.icpdas-usa.com/gw_7473.html?r=Kaan Thank you. Edited 29 Apr 2015 by Emperor Share this post Link to post Share on other sites
Posted 4 May 2015 The N-TRON Switches will do the ModbusTCP form the factory as a standard Share this post Link to post Share on other sites
Posted 23 Mar 2016 hello everybody! i am trying to communicate maple systems hmi and micrologix 1400 ser. b. using modbus TCP/IP. i am using straight trhough ethernet cable with a switch. i am not sure if the parameters in the plc are correct. please check the anexeed images and please tell me if i get mistake thanks! Share this post Link to post Share on other sites
Posted 23 Mar 2016 Generally you won't need a message command (MSG) in the Micrologix. You have correctly set up the Micrologix to use Modbus/TCP and have assigned the N7 register to act as 'Input Registers' when the display requests that information. Share this post Link to post Share on other sites