BMS using PLCs and SCADA

Hello all,

What is your thoughts about implementing BMS systems using PLCs and SCADA.
We did a couple of projects like that with success.
I also see a lot of examples or case studies from various PLC vendors (ABB, Siemens) where they use PLCs for buildings. Recently I came across an application example of a S7-1200 and DALI controllers.

I personally dislike pure BMS solutions mostly because (at least in my country) the market is very closed and the BMS solutions are given only to registered partners. As the market share is small nowadays in Greece, companies are not very fond of making new partners.

I understand that pure BMS systems may have "Special algorithms" for lighting control and HVAC, but what cannot be done with PLCs nowadays?

Regards

BMS = Building management system, I assume?

I'd only ever heard of it as Burner Management System before.

Yes it stands for Building management system.

Honeywell's BMS was a rebranded version of their DCS system.

That said, using technologies that are not the standard practice in an industry mean that you have to make doubly sure that you meet the legal requirements. You can't just say "oh but everyone uses a BMS off the shelf."

There's absolutely no reason you couldn't do it with a PLC. The practical difference between a distributed PLC system and a distributed BMS system is almost nothing - it's really just a case of parallel evolution, so they of course have their own communication protocols (BACNet) and their own software quirks, but if you close one eye and squint a little bit, they're basically the same thing.

The thing that gets me about BMS stuff is how large and non-industrial-looking their devices are. You see this great big brick that's had to be drilled and tapped to a gear tray because it doesn't have a DIN rail bracket, with tiny little screw terminals, and it's a 16 channel input card. And then you compare that to the size of an AB or Siemens input card and just ask yourself "surely technology has moved past that by now". I guess it's just a case of priorities between the different industries - industrial PLC's are under constant pressure to become smaller and easier to mount and wire as we try to squeeze the controls into smaller and smaller cabinets, whereas probably nobody bats an eye if you tell them you need to build a one-off seven metre switchboard for their building services.