Host Engineering Forum

General Category => Do-more CPUs and Do-more Designer Software => Topic started by: davidbgtx on March 03, 2015, 05:19:39 PM

Title: Do-More peer link to ThinkNdo WINPLC ?
Post by: davidbgtx on March 03, 2015, 05:19:39 PM
Can Do-More do peer link with  ThinkNdo on a WINPLC? Please say yes, can't replace all my WINPLC's at once that need to talk to each other.
Title: Re: Do-More peer link to ThinkNdo WINPLC ?
Post by: BobO on March 03, 2015, 08:33:26 PM
Would love to say yes, but I would be lying.

Does T&D support Modbus/TCP?
Title: Re: Do-More peer link to ThinkNdo WINPLC ?
Post by: davidbgtx on March 04, 2015, 08:05:38 AM
T&D documentation doesn't state that (that I can find), but I log data to a SQl database with KepServerEX from T&D WINPLC using converted T&D tags to modbus addressing. So I tried a MRX and "IT JUST WORKS" (don't even need KepServer as a "go between". Haven't tried MWX yet, but it should work as well. Need 1 Do-More to read/write a few tags (about once per second)to each of about 24 WINPLC's (to start, will gradually decrease as I replace WINPLC's with Do-Mores'), do you think it will "bog down" the Do-More?
Title: Re: Do-More peer link to ThinkNdo WINPLC ?
Post by: BobO on March 04, 2015, 08:53:30 AM
Bog down at once per second? No. To be most efficient, create a Modbus/TCP Client for each target. If you use the same client for each connection, the controller has to connect and disconnect from each T&D device, which causes a bunch of unnecessary overhead.
Title: Re: Do-More peer link to ThinkNdo WINPLC ?
Post by: davidbgtx on March 05, 2015, 02:27:38 PM
Bog down at once per second? No. To be most efficient, create a Modbus/TCP Client for each target. If you use the same client for each connection, the controller has to connect and disconnect from each T&D device, which causes a bunch of unnecessary overhead.
Thanks for advice, I would have thought just the opposite and only used 1 Modbus/TCP client. Seems this old dog, still has some new tricks to learn.
Title: Re: Do-More peer link to ThinkNdo WINPLC ?
Post by: BobO on March 05, 2015, 02:36:08 PM
There is some additional overhead to servicing the Do-more client drivers, but it ends up being far less than establishing and terminating a TCP connection to each client each time you talk to it.