Communicating with your heating system
Get ready for the next wave of innovation By Roy Collver Over the last 25 years or so, just about every school district in Canada has made the DDC (Direct Digital Control) system an integral part of their strategy to reduce energy consumption, increase productivity, and monitor the operation of their facilities’ mechanical systems. These things work, but they can be almost completely inscrutable to anyone but the equipment suppliers and the few specialists within a school district who have received the detailed training required to operate and program them. The following excerpt is from a Wikipedia entry, describing one of the very first DDC systems installed back in 1981. “Each remote or Satellite Intelligence Unit (SIU) ran two Z80 microprocessors whilst the front end ran 11 in a Parallel Processing configuration with paged common memory. The Z80 microprocessors shared the load by passing tasks to each other via the common memory and the communications network. This was possibly the first successful implementation of a distributed processing direct digital control system.” Did you all get that? Yes, this was one of the very first systems put together – and the days of job security via “gobbledygook” were born. DDC controls engineers and technicians speak a whole different language than the rest of us, and for awhile, it seemed as if never the twain should meet. Then came “Gooey” – actually GUI (Graphical User Interface), making these systems accessible to the rest of humanity. At first, GUI was disdained by the hard-core control geeks for the same reasons early computer geeks heaped scorn upon the Apple Computer GUI for wasting processing power, memory, and slowing down some key command input functions. But the fact was, the average facilities manager and their techni-
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Ops Talk • Spring 2012
cians could finally just turn on a computer and easily scan the operation of their various buildings, without having to refer to a three-inch-thick manual and wade through lines of code language. I remember those early days, and my experience was that the vast majority of facilities operators pretty much ignored the DDC systems in their schools, only using them as elaborate alarm systems to tell them when something went
ly into these BACnet-capable appliances. Most of them can easily produce clear and comprehensible graphic displays, such as the example shown below, so that facilities operators can grab all the information they need in an instant. This screen shot tells you everything you need to know at a glance, and the BACnet capability means the operator can drill down deeper to get even more information.
wrong. The decreasing cost of computer memory and the increasing power of computer processors, however, have changed everything. Open communication protocols such as BACnet, LON and Modbus have allowed equipment manufacturers to offer easy connectivity directly to DDC systems. BACnet, owned by ASHRAE, is clearly the favourite protocol here in Western Canada for school facilities. DDC suppliers can now tie direct-
So what’s next? Most of the newest innovations have actually been around awhile, but the hardware and software needed to take advantage of them is starting to hit us in wave after wave. Smartphones, iPads and other Tablet devices, lightweight laptop computers, Wi-Fi, Internet – all are being stirred up in the pot right now. With web access available through your smartphone, you can gain complete access to your building’s information from anywhere in the
