Processes for installing and commissioning lighting controls range from very good to nonexistent. Simple and proper setup depends on a number of factors including standards, compatibilities, cost and time.
Barriers associated with installation/commissioning assurance include:
Difficult, time-consuming and expensive installation
Dimming controls and automatic shut-off controls vary in cost and difficulty of use. Dimming systems are expensive to acquire and often difficult to install. Commissioning currently available photosensors is prohibitively time-consuming, meaning they are almost never installed. Installation of shut-off controls in new construction is relatively simple and can be accomplished easily by trained technicians. However, penetration of shut-off controls in retrofit applications is limited due to factors such as perceived hassles and added costs to replace existing manual controls.
Lack of consistent, thorough standards
0-10V control is by far the most common control signal used for dimming ballasts. While control equipment used in the entertainment industry follow a 0-10V control standard set by ANSI, no established, consistent standard exists for ballasts used in commercial and industrial applications. Different manufacturers support different features, often deviating from the entertainment industry standard. Even if the ballast control did conform, the current standard does not detail the functional relationship between the control signal level and the light output level of the ballast. For example, a 5V signal from one ballast manufacturer may result in a 30% dim level, while that same 5V signal may result in a 50% dim level for another manufacturer's ballast. Controls must be field-calibrated to work consistently, and mixing ballasts from different manufacturers under the same controller will likely result in different light levels.
Inadequate application guidelines for successful performance
Poor field performance is often a result of the lack of application guidelines. Little or no information is given to installers concerning proper cabling or wiring installation practices for dimming ballasts. Installation of automatic shut-off controls in retrofit applications also presents problems because of insufficient documentation and guidelines.
Zoning logistics inflexible and/or laborious
For conventional analog input ballasts, the task of zoning must be done when the ballasts are installed. This makes the zoning difficult to change if the space is renovated for a different purpose. For the newer direct digital control ballasts, zoning is done after installation as part of commissioning, making rezoning much easier. But zoning is still a laborious task because each ballast location must be manually identified, which increases costs and the potential for problems.
Uncertainties about dimming requirements and the presence of manual controls
Automatic dimming during occupancy is an area of uncertainty because principles have not been established for occupant acceptance of the level and rate of dimming. For both dimming and automatic shut-off controls, engineers and facility managers often are hesitant to install manual controls because they may assume that these overrides will be used too often, eliminating any energy savings.
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