Tech Posted August 19, 2019 Report Share Posted August 19, 2019 Dear all, We communicate 10 nodes through rs485 communication in v700 port 1..the problem is if my one divice is failture means other 9 nodes getting delayed..kindly provide solution RegArds Mohamed Quote Link to comment Share on other sites More sharing options...
MVP 2021 Ausman Posted August 19, 2019 MVP 2021 Report Share Posted August 19, 2019 You will likely have a timeout and number of tries overlap error. For any 485 comms you need to allow for the TOTAL time the plc may spend trying to contact a node, before you switch to the next attempt. A simple example.... If you have a timeout of 1 second and 3 retries, then if there is an error on one node it will take a little over 3 seconds for the plc to ignore the error and reset the connection attempt ready for the next one. Your interval/method of triggering the next call to any node must allow for this possibility. To speed things up you often only do a single try, on the reasoning that if it fails once it will fail again. cheers, Aus Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.