Foreword: My youngest daughter attends a new public charter where I volunteer more time than I can afford as the “Technology Guy.” The students were issued on day one Chromebooks and Kindles, and they do very limited work with paper of any sort. I worried would all the technology and apps come together, but recently she commented to me “Dad sometimes we learn so much I can barely keep up.” She never said this before. I think the technology is working.
Just ten years ago, a white board was the only media presentation method for most classrooms in the U.S., and automation of any type was seen in less than 10 percent of all classrooms. Having been part of hundreds of classroom refresh projects over the last few years I see the budgets, speak with administrators, work with support technicians, and chat with students using the spaces, so I have a ground level experience of what really makes sense for practical cost effective automation design in most of those rooms.
To start lets identify three groups that classrooms fall into from our installation experience;
- Standard use classroom (90 percent) — seen in the title image above
- Mid-sized multimedia and distance learning classroom (20 percent)
- Large theater classrooms (5 percent)
This breakdown is based mostly on automation complexity (not size necessarily). Type 2 and 3 are very custom, but represent a small group, so we will focus on the 90 percentile group that generally gets the least attention because of the perceived high costs for automation.
At least two factors have greatly effected the design of the standard classroom over the last few years: conservation measures mandated by governments, and a significant drop in automation costs as manufacturers design for these spaces. Because of the need for green, both HVAC and Lighting management have become much more common in these spaces where it was until very recently never considered or affordable.
If you are considering a classroom refresh, or designing new spaces, please let me share some real experience that may affect your plans. Here is what you should include in your space planning that will allow you to get the most for the least cost (you may be surprised how much is possible);
- Automation — Use a local automation controller that is Ethernet connected, with on-board lighting control and occupancy inputs. Central automation (while better than no automation) increases the single point of failure concerns as well as long cable runs. I recommend distributed intelligence because it adds room located lamp control relays and Input/output points for greater local automation and sensor inputs. Many typical controllers are able to manage multiple rooms, so don’t assume one controller per room.
- Lighting — Use a simple four-button, low-voltage switch on wall near door. Three buttons to control individual zones on/off, and the bottom button is All Off. Optional duplicate switch(s) near second door and or instructor station. If any zones are made dimmable, then the assigned button uses press and hold functions to dim up and down instead of just on/off:
- Front zone 1 to light instructor and whiteboards. Turn this zone off for projectors or display presentation. Button 1 on wall switch.
- Main lighting for room on zone 2. Turned on with occupancy sensors and wall switch button 2.
- Lighting in front of windows extends main lighting on zone 3, but switched off to harvest light on bright days. Button 3 on wall switch.
- If no windows, then zone 2 and 3 will both be main lighting on alternating rows. Only one row will turn on with occupancy.
- Optional 4th zone can be used for podium/instructor lighting, door lamps, or custom wall and bookshelf lighting (use button 4 on switch instead of All Off).
- Occupancy — Sensor turns on main lighting on zone 2 (and no others). User then chooses additional lighting if desired. There is a growing trend not to turn ON lighting automatically, but to instead require the user to activate lighting IF desired. Safety, security and common sense should always be used when making a decision not to automate lighting, of course.
- Vacancy turns off all lighting. You need good coverage for motion, so consider overlapping sensors to ensure full and complete coverage.
- Additional possibilities for lighting automation include lights on for fire or security alarms. While a stand-alone occupancy controlled system is greener than no system, don’t pass on connected lighting.
- HVAC — The automation system should be connected directly or indirectly to the Building Automation System (BAS) to share occupancy status with HVAC control of that space. BACnet is or should be the method of communication. If a BAS is not in use, then consider an AV or light monitoring application to enable remote control, or alert staff when equipment fails.
- Presentation Automation — Consider using an 80″-plus display. For media input use, Google Chromcast (or similar), which will automatically turn on the display when a laptop selects it (basically the same works for newer projectors). I push towards the larger displays to get away from projectors and the additional support needs they bring, but you often need 80″ to make the switch. The display will turn off with no use automatically.
- More is better — IF there is a little more budget, then here is where you can spend it by replacing the passive display with an active whiteboard. You could pull HDMI cable to the instructor location, but the cable connections are high failure points and tethers the instructor to the podium, so the Chromecast is the laptop interface. And yes, the students can also connect to the display using their tablet or laptop. There are more expensive ways to connect the presentation source to the display via switchers, but this room design is for the masses, not the elite.
When this simple design is employed the room is green, easy to use for instructors, easy to support by the AV staff, and our, perhaps most importantly, acceptably cool by our tech savvy generation of students.
In addition to Richard’s day job, he is founder and moderator of the Open Source Classroom Automation site on Google.