C-Bus to BACnet Protocol

Can anyone help with communications from C-Bus over a BACnet protocol. As an electrician I don't have the full gist of BACnet protocol. I think it uses RS485 open protocol ? I need to interface a C-Bus network to talk with a BMS over BACnet. One of the problems is that I need to send many status' to the BMS to control many A/C's in various areas, depending upon the PIR's status for that particular area. One way I can do is by using bus couplers and send "dry" contacts, to which the BMS will need the capacity for these "dry" inputs. Does anyone have any ideas? or other interface ideas to help ?

 

Hey Macka,

Have a look at a post that 2SC made the other day:

http://www.cbusforums.com/forums/showthread.php?t=3920&highlight=BACNet

This might help steer you in the right direction regarding interfacing C-Bus to BACNet

Darpa

 

If you want to do further research into the BACNet protocol, then have a look at these websites:

http://www.bacnet.org/

http://en.wikipedia.org/wiki/BACnet

I don't really know anything about BACNet, but from everything I've read, it is simply a protocol to define how devices communicate, and is capable of being transmitted/received over many different forms of network media, including, but not limited to, RS232, RS485, Ethernet, etc.

 

Can Scheduler handle BACnet ?

Darpa,

Apparently Scheduler has the ability to communicate via BACnet, modbus etc. But I would need a stand alone PC running scheduler to do the "handshaking"?????

 

I have no idea Macka, I'm out of my league.
I would assume that you would not need another seperate schedule+ PC just for BACNet if you have a high-level CBus-BACNet gateway, but thats just a guess, not an answer.
Give it a day or two and someone far smarter than me will hopefully give you the answers you seek

 

Clipsal (CIS Marketing) have had their head in the sand re exposing C-Bus information to the larger world via open protocols like BACnet and LON for about 300 years so at the moment there is no quick answer.

To be a little fair on the subject BACnet and LON are not simple flat structures when it comes to lining up one technology / protocol from one manufacturer to the technology / protocol of another manufacturer. BACnet can be implemented at different levels of conformance to standards, lining up with 4 of the 7 layers of the ISO model for Open Systems Interconnect (OSI) - and LONworks say they line up with all seven layers of the OSI model.

It is very interesting that these questions are starting to be asked on a users forum. Maybe some in CIS might wake up and hear the news.

PS if you can get away with low level interface 1-30 maybe 40 points then go that way for the moment.

I just fell off the soap box and hurt my ankle - yell if you would like any more info on the subject...

 

If you are interested in a High Level interface I have heard whispers that there is a C-Bus OPC Server in development (not sure if it should be mentioned yet, but plenty of people seem to know about it). With this you can run the C-Bus OPC Server on a PC and a BACNet OPC Server on the same PC with a Server bridge to make them communicate to each other. This same setup can probably work for any other protocol out there.

The C-Bus OPC Server is not available yet, although I have heard whispers that it is currently being tested and may be on the market in a couple of months. Maybe too late for your purposes.

Don't hold me to any of what I have said above, I'm no longer a Clipsal employee and may have spoken out of turn. (Site admins feel free to delete this post if needed)

 

Hey Richo

OPC would be a nice start, and would assist some programmers out there to make many C-Bus installs relevant to the larger world. If this is the case it would be a long time coming...

OPC is a little dated, however ,a start is, "a start".

Let's see

Take care brother !

 

Dated, but very widely supported. I doubt there is another high level protocol that can give you access to such a wide variety of hardware and software products.