Trane.. Anyone successful with it?

cma

Old Trane system communicating via MODBus (I believe? system programmed by previous integration company and worked sporadically) being replaced by new unit that I am told uses BACnet? Can't find much info on it and the HVAC contractor hasn't been able to help at all.

cma

Found this article.. Anyone here know anything about this?

http://www.automatedbuildings.com/releases/aug10/100810121707fieldserver.htm

ericmedley

It's just using either a BACnet or LON gateway(s) to hook into a building environmental control system. That's been around for a while. Just search for those protocols and/or download one of the AMX modules for BACnet for clues or even use.

cma

I don't see an AMX BACnet module anywhere..

Joe Hebert

cma wrote: »

I don't see an AMX BACnet module anywhere..

That's because there isn't one.

I would forget about interfacing with BACnet. A BACnet to Modbus gateway is the way to go. I've used Modbus several times in the past with various HVAC systems and water feature systems. I'd have to look through my jobs and notes but I'm pretty sure Trane was one of them.

There is an AMX Modbus module available which also includes the source code. If you can't find it on the web site, email AMX Tech Support and ask for it.

You need an HVAC contractor that knows how to map Modbus points (holding registers and coils) to BACnet points. It can sometimes get tricky for the HVAC guy keeping the BACnet/Modbus points in sync if the HVAC system has its own software for control and feedback.

There is an extra cost involved for the HVAC contractor since he needs to provide the Modbus gateway hardware (which sometimes has a licensing cost associated with it as well) and there is time involved to map the BACnet points to Modbus points. It's a cost that can be pushed on to the client but it does require the HVAC contractor to go the extra mile to allow integration.

If you have an uneducated/unwilling HVAC contractor, then I would run. Sometimes the best decision is to say no. If the client wants you to interface with the HVAC badly enough, then the client will push the HVAC contractor to cooperate or find a contractor that is willing and able.

Good luck.

ericmedley

Joe Hebert wrote: »

That's because there isn't one.

I can confirm this. I dug around on the AMX site and didn't find one either. I did a file search in my projects and found one but my notes also say it's very buggy. It didn't end up in my code. I, like Joe Hebert, ended up using the MODBUS one and a gateway. I will also agree with Joe in that I have done something like 10 of these systems and hated them all. They don't show up in my commercial jobs anymore as most folks have moved on to newer systems that utilize various IP based 3rd Party control APIs.

I will also amplify Joe's advice: Run - don't walk away from it.

Sorry for the dead-end advice on the module.

cma

OK, I found the BACnet module discussed in this thread..

http://www.amxforums.com/forum/technical-forum/2968-bacnet-hvac-control-interface

Running blind on it though seeing that L_Cubed has dropped off the forum and I can't reach him.. A Modbus translator is an option but the old interface was Modbus and was unreliable so the owners and HVAC contractors are weary of another Modbus interface.

vining

cma wrote: »

OK, I found the BACnet module discussed in this thread..

http://www.amxforums.com/forum/technical-forum/2968-bacnet-hvac-control-interface

Running blind on it though seeing that L_Cubed has dropped off the forum and I can't reach him.. A Modbus translator is an option but the old interface was Modbus and was unreliable so the owners and HVAC contractors are weary of another Modbus interface.

Larry Landaeta works for AMX now, I think Eastern US Sales Engineer. I believe he sold that module though but you give track him down through AMX and find out.