Author Topic: Modbus RTU performance  (Read 6442 times)

zif

  • Guest
Modbus RTU performance
« on: September 06, 2002, 08:54:42 AM »
Hi All,

I would like to know approximately what would be a response time from a Modbus slave after a command was sent from a T100MD888. The network would consist of one master and three slaves (two VFDs that would return 9 registers and one remote I/O with 10 registers). I don't have any T100MD888 handy to measure the response, so any kind of input would be greatly appreciated!

Thanks,
zif
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »

support

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 3171
    • View Profile
    • Internet Programmable PLCs
Re: Modbus RTU performance
« Reply #1 on: September 07, 2002, 01:59:59 PM »
The response time will depend on how long your RTU device takes to respond to an incoming command and you will have to check with your VFD or remote I/O manufacturer for such data.

Once the slave start sending back the response to a MODBUS READ, You can calculate totol transmission time of the response message by computing  the number of bytes transmitted by the slave in response to the MODBUS 03 command (read) by the baud rate.

The MOBDUS command can be found at: www.modbus.org.
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »
Email: support@triplc.com
Tel: 1-877-TRI-PLCS