Smart Building Controls vs. Home Automation
Building automation and technology are all around us and in every aspect of our lives whether we realize it or not. At home, you have smart thermostats, TV’s and phones. At work, you may have an automation controls system that tells the lights to turn on at a specific time and the A/C to turn off once it reaches a precise temperature. Whether you were aware or not you come into contact with these systems every day, we are now going to cover the different types of control systems out there like pneumatics, analog, electromechanical, digital, and direct digital control and just what it is they do.
Pneumatics are one of the oldest types of control systems out there. Pneumatic systems work by compressing air, drying the air to remove moisture where it’s then pushed down main line piping. Spread out along these main lines are devices that take the air flow and regulate the air passing through them to a branch line. The branch line sends signals to devices, controlling how much air will enter that new device. The great thing about pneumatics is that, even though it's one of the oldest types of control system tech these types of systems generally have long operating lives and require little maintenance.
Analog control systems are still everywhere and still super reliable like pneumatics. Before digital displays became the norm, physical dials and buttons were the controls for an analog system. Older toaster ovens have knobs; newer ones have digital displays. Think about it like this...when you turn that knob to increase the heat on an older toaster oven you are sending resistance to a circuit. That resistance causes a control device like a valve or relay inside the toaster to react and raise the heat.
Electromechanical control systems refer to systems that use an electrical signal to create mechanical movement. They typically consist of multiple relays, timers or counters wired together inside a panel. Many unit heaters contain a temperature element which reacts to a change in temperature. The element expands when the temperature has a significant variation causing a circuit to open or close. This closing or opening of the circuit will either turn the heating unit on or off.
Digital control systems are everywhere these days. Smart thermostats, televisions, musical keyboards, they all have one thing in common...they contain a microprocessor board that receives a signal based on your interaction with that device. That signal then changes the corresponding output to your desired action.
Direct Digital Control
These are digital systems that are networked together and are also known as DDC. DDC brought two game changers to the table when it comes to building automation systems, direct digital control, and microprocessor control. Before direct digital control systems relied on analog inputs which were prone to calibration errors and resulted in several degrees off the actual temperature in a space, DDC gave the flexibility to maintain the “offset” on their temperature sensor. DDC also enabled the changes in programs to be revolutionized by software instead of dip switch settings and slot cards! In the famous words of Drake, “We started from the bottom now we’re here.”
In their own way, each of these types of controls systems has their pros and cons. It's essential in the controls industry to know where you came from and how in some cases each of these types of control systems may apply to your next project.