Posted 30 Oct 2010 LS G7MU with ATV31 Hello, I'm using modbus rs485 with LS/LG PLC G7MU to control several inverters ATV31 Schneider. I can start, stop, send speed ref, receive feedback etc, one by one. The problem is I can't start all inverters in the same time, together. If I send start signal on the same time for all inverters, communication become error. Then I put some delay, after send start to inverter-1, delay 10sec, then start inverter-2............... The condition is same to receive feedback signal from inverter, must one by one. Each inverter has its own ID. Please help if any information, how to start all inverters together on same time. Thank you Share this post Link to post Share on other sites
Posted 1 Nov 2010 IIRC, with modbus, you can only communicate with 1 device at a time. My suggestion is to trigger the start of the first drive, when your comm port is done with that command, start the next drive and so on... Hope this helps. Share this post Link to post Share on other sites
Posted 5 Nov 2010 Hi Jennings, Thanks for your help. Share this post Link to post Share on other sites