What device to use to get values from a Modbus device into TAC Vista.

Issue

  • What device to use to get values form a Modbus device in to TAC Vista
  • Get data from Modbus meter to BMS system running Vista.

Product Line

TAC Vista

Environment

TAC Vista

TAC Xbuilder

TAC Xenta server 731/913

Cause

TAC Vista can not talk Modbus directly so you need to use a gateway controller.

Resolution

Xenta firmware version 5.1.4 and earlier only two controllers had Modbus communication capabilities:

  1. Xenta Server 731  For details see
    TAC Xenta 711/731 Web Server and Controller
  2. Xenta Server 913 For details see
    TAC Xenta 913 LonWorks Gateway

Starting with Xenta firmware version 5.1.5, all Xenta Servers are now capable of communicating on a Modbus network both via TCP/IP and RS-485.  This includes Xenta 511, 527, 701, 711, 721, 731, 913.

Note: Older Xenta Server devices built before firmware 5.1.5 have the capability of using Modbus over RS-485 once they have been upgraded even though the terminals are not labeled on the device. For information on how to wire these devices reference a newer Xenta Server that does have the RS-485 A terminals labeled or see Lessons Learned #4994.