The below questions can help narrow down selection of an appropriate control strategy:
Surveys taken include:
2003 Ducker Research / Watt Stopper Lighting Automation Study
Methodology
Study Focus
Research Question
Average Respondent Answer
2004-2005 ZING Communications/ LCA Dimming Study
Methodology
Study Focus
Research Question
Average Respondent Answer
2005 Square D Bulls Eye Study
Methodology
Study Focus
Research Question
Average Respondent Answer
List of common applications with typical application needs and control strategies.
| Cafeterias or Lunchrooms | Occupied occasionally |
| If | Consider |
| Daylighted | Daylight-driven dimming or on/off control |
| Occupied occasionally | Ceiling-mounted occupancy sensor(s). Make sure minor motion will be detected in all desired locations |
| Classroom | Usually occupied / Occasionally occupied |
| If | Consider |
| Multi-tasks like overhead projectors, chalkboard, student note taking and reading, class demonstrations | Manual dimming in combination with occupancy sensors |
| Occupied by different students and teachers | Ceiling-mounted occupancy sensor(s) and manual dimming. Make sure that minor motion will be detected |
| Lights left on after hours | Centralized controls to schedule lighting in combination with occupancy sensors |
| Computer Room | Usually unoccupied |
| If | Consider |
| Lights are left on all the time | Multiple occupancy sensors to ensure minor motion detection, with manual dimming. Be sure that equipment vibration and air flow will not falsely trigger the sensor |
| Conference Room | Occupied occasionally |
| If | Consider |
| Multi-tasks from video-conferencing to presentations | Manual dimming (possibly preset scene control) in combination with occupancy sensors |
| Small conference room | Wall or ceiling-mounted occupancy sensor |
| Large conference room | Ceiling-mounted occupancy sensor(s). Be sure that minor motion will be detected in all desired locations |
| Gymnasium or Fitness | Usually occupied |
| If | Consider |
| Requires varied lighting levels for activities | Manual dimming and occupancy sensors. Be sure that the Heating Ventilation Air Conditioning system will not falsely trigger the sensor. |
| Hallways | Any |
| If | Consider |
| Occasionally or usually occupied | Occupancy sensors with elongated throw. Be sure that coverage does not extend beyond the desired area and that key entry/exit locations are adequately covered |
| Daylighted | Daylight on/off control |
| Health Care - Examination Rooms | Occasionally occupied |
| If | Consider |
| Different lighting needs for examination | Manual dimming |
| Small areas | A wall box occupancy sensor |
| Health Care - Hallways | Usually occupied |
| If | Consider |
| Daylighted | Automatic daylight-driven dimming |
| Requires lower lighting level at night | Centralized controls to lower lighting levels at night |
| Health Care - Patient Rooms | Usually occupied |
| If | Consider |
| Different lighting needs for watching television, reading, sleeping and examination | Manual dimming. Occupancy sensors are not appropriate |
| Hotel Rooms | Occasionally occupied |
| If | Consider |
| Use primarily in the late afternoon through evening for sleeping and relaxing | Manual dimming. Consider wall-switch occupancy sensor in restroom for lights and/or exhaust fan |
| Laboratories | Usually occupied |
| If | Consider |
| Daylighted | Automatic daylight-driven dimming in combination with multiple ceiling-mounted PIR occupancy sensors. |
| Laundry Rooms | Occasionally occupied |
| If | Consider |
| Requires high light levels, yet lights are usually left on | Occupancy sensors |
| Libraries - Reading Areas | Usually occupied |
| If | Consider |
| Daylight... | Automatic daylight-driven dimming |
| Lights left on after hours | Centralized controls or ceiling-mounted occupancy sensors. Use 30-minute time delay |
| Libraries - Stack Areas | Occasionally occupied |
| If | Consider |
| Stacks are usually unoccupied | Ceiling-mounted PIR occupancy sensor(s) and bi-level switching |
| Lobby or Atrium | Usually occupied but no one ownsthe space |
| If | Consider |
| Daylighted and lights should always appear on... | Automatic daylight-driven dimming |
| It isn’t a problem if lights go completely off in high daylight... | Automatic daylight-driven dimming or on/off control |
| Lights are left on all night long, even when no one is in the area for long periods | Centralized controls or occupancy sensors. Be sure that minor motion will be detected in all desired areas. Incorporate bi-level switching. |
| Office, Open | Usually occupied |
| If | Consider |
| Daylighted... | Automatic daylight-driven dimming and ceiling-mounted occupancy sensors |
| Varied tasks from computer usage to reading | Manual dimming |
| Lights left on after hours | Centralized controls and/or ceiling-mounted occupancy sensors. |
| Office, Private | Primarily one person, coming and going |
| If | Consider |
| Daylighted... | Manual dimming or automatic daylight-driven dimming and wallmounted occupancy sensors |
| Occupants are likely to leave lights on and occupants would be in direct view of a wall box sensor | A wall-box or ceiling-mounted occupancy sensor |
| Occupants are likely to leave lights on and partitions or objects could hide an occupant from the sensor | Ceiling-mounted occupancy sensor |
| Photocopying, Sorting, Assembling | Occasionally occupied |
| If | Consider |
| Lights are left on when they are not needed | Occupancy sensor. Be sure that machine vibration will not falsely trigger the sensor. |
| Restaurant | Usually occupied |
| If | Consider |
| Daylighted | Automatic daylight-driven dimming |
| Requires different lighting levels throughout the day | Manual dimming (possibly preset scene dimming) |
| Requires different lighting levels for cleaning | Centralized control |
| Restroom | Any |
| If | Consider |
| Has stalls | Ceiling-mounted occupancy sensor that provides for full coverage |
| Single toilet (no partitions) | Wall switch or ceiling-mounted occupancy sensor |
| Retail Store | Usually occupied |
| If | Consider |
| Daylighted... | Automatic daylight-driven dimming |
| Different lighting needs for retail sales, stocking, cleaning | Centralized controls or preset scene dimming control |
| Warehouse | Aisles are usually unoccupied |
| If | Consider |
| Daylighted | Daylight-driven dimming or daylight on/off control |
| Lights in an aisle can be turned off when the aisle is unoccupied | Ceiling-mounted PIR occupancy sensors with elongated throw. Select a sensor that will not detect motion in neighboring aisles, especially when shelves are lightly loaded. |
The first primary decision after defining the load and the application goals is whether to switch or dim the load. Switching and dimming are stand-alone strategies but are often used in the same facility, and may be integrated in the same control system.
| Method | Switching | Dimming |
| Primary Use | Energy management | Visual needs |
| Basic Function | Turn lights on or off | Change light output with smooth transitions between light levels |
| Benefits | Utility cost savings | Occupant satisfaction, flexibility, utility cost savings |
| Advantages | Relatively inexpensive and simple to commission | Can set light output at any level within available range, greater user acceptance due to smooth transitions between light levels |
| Disadvantages | Lower user acceptance in occupied spaces with stationary tasks due to abrupt, noticeable changes in light level | Higher installed cost, and can require more sophisticated commissioning |
The traditional approach is to divide the building into series of control zones. Each zone consists of a lighting load controlled by a single controller. A lighting load is usually one or a group of luminaires.
Local control:
Central control:
The control scheme can be designed with local systems and a centralized system working together as layers. Both local and centralized systems can be integrated into building automation systems for control of lighting and HVAC (Heating Ventilation and Air Conditioning).
Manual lighting controls range from a single switch to a bank of switches and dimmers that are actuated by toggles, rotary knobs, push buttons, remote control, and other means.
Manual controls can be cost-effective options for small-scale situations. However, as the size of the lighting system grows, manual controls lose their cost-effectiveness. In addition, manual controls often waste energy because the decision to shut off the lights when they are not needed is based entirely on human initiative.
| Strategy | Manual vs. Automatic |
| Occupancy sensors | Turn the lights on or off automatically based on whether space is occupied |
| Scheduled automatic shut-off at end of workday switching panels, time-clocks or building automation system | Turn selected lights on or off automatically based on schedule when space is predictably unoccupied |
| Scheduled automatic shut-off of select loads (bi-level switching) during peak demand periods, time-clocks or building automation system | Turn off one or two lamps in each fixture or checkerboard fixtures automatically for load shedding during peak demand periods |
| Bi-level switching using wall switches controlling lighting system layered as two separate circuits | Turn selected circuit on and off manually to achieve ON, 50% light level, and OFF |
| Multilevel switching using photosensor and low-voltage relay | Turn the lights off automatically based on available ambient daylight |
| Strategy | Manual vs. Automatic |
| Dimming control of smaller loads using wall-box and remote dimmers | Adjust light output manually based on space need or personal preference |
| Dimming control of larger loads using control stations and dimming panels | Adjust light output manually based on space need or personal preference |
| Daylight harvesting using photosensor, controller and dimmable ballast | Adjust light output automatically to maintain target light level as daylight enters space |
| Adaptive compensation using dimming panels and scheduling device such as time-clock | Adjust light output automatically to provide lower light levels at night based on studies about human lighting preferences |
| Peak shaving and load shedding using dimming panels and scheduling or control device | Adjust light output automatically during peak demand periods and/or manually based on utility request to curtail load |
Typical: Basic Controls
Typical: Advanced Controls
Enhanced Automation: Centralized Controls
A key step in designing a lighting control system is to determine the degree of control over the lighting system, which means breaking the load up into zones.
Establishing smaller zones increases control accuracy and flexibility but also increases cost.
By determining the most appropriate control strategy for the application using these guidelines, one can specify control systems that provide the right amount of light where it’s needed, and when it’s needed-thereby minimizing optimizing operating costs and increasing user satisfaction.
Davmark™ can help you achieve these requirements.