Xenta 913 -- inet to modbus/IP

[eldowan]

In my current building, we have a large installation base of TAC inet devices, along with various bacnet and modbus devices as well.

My current concern is finding a way to bring all of the inet devices into our BMS via modbus over IP.

Currently our setup consists of multiple 913s polling the inet devices, and communicating to a BCX9000 to enable us to communicate via bacnet. However, the BMS doesn't natively talk bacnet, so we have to employ an OPC server. As far as I can tell, this just adds more points of failure and increases latency.

Looking through the Xenta 913 manual, it appears that the device can act as a gateway between inet and modbus. If possible, I would like to configure my 913s to allow our BMS to directly poll the xentas without going through an OPC server and a BCX.

Specifically, if I'm reading this quote from the 913 datasheet, I think this is what I'm looking for:

http://208.69.45.150/casefiles/7305/..._Datasheet.pdf
The Xenta 913 can be configured to act as a slave on a Modbus and/or J-Bus serial network to allow an external master to read and write values from an I/NET or LON control system. Both the RTU and ASCII protocol formats are supported. A number of Modbus registers can be connected to a corresponding set of LON network variables or I/NET points to allow the master device to exchange values with the BMS via
the Xenta 913, which acts as one or more slaves to reflect BMS values as Modbus registers.

The Xenta 913 can be configured to act as a client to a Modbus TCP server to allow monitoring and control of one or more slave devices via an I/NET or LON control system. Both the RTU and ASCII protocol formats are supported. A number of Modbus registers can be connected to a corresponding set of LON network variables or I/NET points to allow one or more slave devices to be monitored and controlled. The Xenta 913 acts as a network client, exchanging the required register values with the slaves via a Modbus TCP server.

Is this a feasable option?

Thanks all for any insight

[ClintCronwright]

Hello,

I was wondering if you found a solution to your query above?

I ask because I am currently having a similar problem in that I know the TAC Xenta 913 can be set as a Modbus slave but I can not find any documentation on the details of how to do this (even the Xenta engineer I have been in contact with is struggling with the detail and tells me that there is no more documentation).

The main problem is that once it is set as a slave and the template created for making the room sensor available to Modbus, there is no mention of the Xenta's ID anywhere and the Master is unable to communicate with the Xenta (using known working port, cables, etc), though both the engineer and I have been taking guesses to the ID of the Xenta as we can't find it.

Hopefully you found a solution and can shed some light?

Clint.

[eldowan]

Hello,

I was wondering if you found a solution to your query above?

I ask because I am currently having a similar problem in that I know the TAC Xenta 913 can be set as a Modbus slave but I can not find any documentation on the details of how to do this (even the Xenta engineer I have been in contact with is struggling with the detail and tells me that there is no more documentation).

The main problem is that once it is set as a slave and the template created for making the room sensor available to Modbus, there is no mention of the Xenta's ID anywhere and the Master is unable to communicate with the Xenta (using known working port, cables, etc), though both the engineer and I have been taking guesses to the ID of the Xenta as we can't find it.

Hopefully you found a solution and can shed some light?

Clint.

Clint,

Unfortunately, I have made no headway on this issue.
I'm going to continue to research and try to figure this out, as it seems it should be possible.

Should I find a solution, I'll reply here, I hope you'll do the same.


Good luck,
eldowan