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Lighting Control Guide

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Lighting Control Guide www.thelia.org.uk LIGHTING CONTROL GUIDE. LIA Copyright © 2018. All information stated within this brochure is correct at time of publication – October 2018. www.thelia.org.uk OBJECTIVES OF THE GUIDE The aims of this guide are: To provide an appreciation of the benefits of lighting controls • To demonstrate that the benefits and abilities extend beyond electricity use reduction • To make the terminology of lighting controls more familiar • To inform those who are considering the use of lighting controls • To help match controls and light sources to ensure optimum results • To show where expert and reputable advice may be sought • To provide an introduction to a deeper understanding of the subject through training • To provide a decision tree to assist in the selection of the most suitable lighting controls The creation of this guide would not have been possible without the valuable help provided by members of the LIA Controls Equipment Technical Committee (CETC). Automatic lighting controls are often thought to be a dark art. In reality, they work in the background to manage the lighting without fuss. You can rely on a number of reputable suppliers to sort out the details to suit your application. Just explain how, and when, your business works and they will design the best control strategy and system for your needs. www.thelia.org.uk INTRODUCTION This guide has been structured to give the reader a logical progression through the subject of lighting controls. The subject is divided into a number of sections, which are defined in the table below. Each section can be read independently, and links will guide the reader to any logical connections, both within this guide and to other relevant sources. NAVIGATING THIS GUIDE Route to determine the control type for the application. EVOLUTION OF CONTROLS FOR LIGHTING This section provides the context for the guide and begins to familiarise the reader with the reasons for using lighting controls. It describes the origins of the solutions and products available today, while demonstrating that it is an established and reliable industry. BENEFITS Lighting controls are not only provided to reduce electricity use; there are much wider benefits. They can be the means to deliver good lighting designs; to set moods and ambience. Controls ensure that the right light is provided in the right place, at the right time. TECHNIQUES There are a number of ways to control lights; from simple wall switches to fully networked management systems. This section describes the various ways lights are controlled both manually and automatically; including daylight references and occupancy control. APPLICATIONS Different building types and accommodation require different lighting control solutions. The most common applications are described and appropriate controls suggested. Sub- headings include offices, industry, schools, hospitality, museums, floodlighting and shops. TECHNOLOGIES A brief technical description of generic lighting control products and systems is provided in this section. All the component parts of a lighting control system are introduced, including manual overrides, sensors, lighting control modules, software and interconnections. STANDARDS AND REGULATIONS An overview of the standards, regulations and guides that are relevant to the specification, application and use of lighting controls. A number of links to Government and professional bodies are provided here. GLOSSARY A dictionary of lighting and control terminology. www.thelia.org.uk NAVIGATING THIS GUIDE www.thelia.org.uk EVOLUTION OF CONTROLS FOR LIGHTING Lighting controls have existed for as long as we have had electric artificial lighting. However, today the term lighting controls is generally taken to refer to some form of electronic, or automatic solution, rather than the simple, mains ON/OFF switch. This section is intended to create a context for the understanding of lighting controls by explaining their origins, and how they have developed over time; both technically and functionally. Lighting Controls - the two branches and how they came about The first lighting controls can be traced to the theatre / entertainment world where there was a need to vary light output as well as to turn it ON and OFF. Initially largely manual in nature, theatrical controls evolved into highly complex systems and began to spread to wider - but related - applications. This branch has become known today as scene setting lighting controls. More recently - from the late 1960s onwards - automatic lighting controls entered the commercial built environment. The first systems were little more than an electronic switch that allowed the use of pushbuttons and extra low voltage wiring. The first energy crisis in the mid-1970s brought energy use in buildings into focus for the first time and gave purpose to this branch of the lighting control evolution - to reduce lighting electricity consumption. The two branches of lighting controls familiar to the built environment are, therefore: - Scene setting and Energy Saving Dedicated theatrical control systems continued to evolve separately, but today they have returned to influence the main stream market. In order to assist the designer to select the most suitable lighting controls solution for the application, a decision tree is provided for this purpose – follow this link. Scene setting The applications related to theatre lighting that led to scene setting lighting controls moving into the built environment were auditoria, lecture theatres and conference facilities. The term scene setting was derived from the fact that the systems generally allowed the user to select a specific lighting effect; normally by pushing one button. This action would set the various lighting circuits into a pre-set state - ON, OFF, or at a specific dimmed level. These systems were usually manually operated and offered a wide range of static scenes - i.e. once selected the lighting remained fixed until another scene was chosen. Scene setting systems also dictated the choice of lighting source because not all could be readily dimmed. Even today there are restrictions on certain light sources with respect to their control. These systems were seen to be an integral part of the lighting design and often specified by the lighting designer www.thelia.org.uk Energy saving The early systems developed to control the use of lighting electricity relied heavily on the use of localised switches overlaid with an automatic function that ensured lighting was turned OFF when the building was expected to be empty. These functions included day light levels and time of day. Most of the early energy saving lighting control systems were retrofitted into existing installations and therefore had to be economical to install; they also only needed to be able to turn lights ON and OFF. Dimming had not yet become practical in the commercial building world. And, in stark contrast to the scene setting branch, energy saving lighting controls generally ignored the lighting design. Little or no notice was taken of the original design intent. This was especially true when pull switches were fitted to individual fixtures, allowing staff to choose which lights were ON and which were OFF. The resulting ‘non-uniform’ lighting levels were the subject of much debate (back then) in the world of lighting designers. The impact on the original lighting design was, however, somewhat relieved by the fact that most of these systems gave individual users far more control of their local lighting. This led to higher satisfaction being observed in affected staff, and avoidance of the design issue. +25% +50% +60% +75% No dimming Manual PIR + manual Daylight linked Daylight linked dimming dimming dimming dimming + PIR Convergence The two branches of lighting control began to converge when dimming became a practical element of the energy saving systems. The introduction of the dimmable high frequency electronic ballast for fluorescent lighting was the enabling technology. As already mentioned, the past scene setting systems were all about dimming and levels and energy saving systems relied on ON and OFF commands. Now the dimming function was easily implemented in the building wide lighting controls; the basic functions of a light were no longer just ON and OFF but DIM or BRIGHT according to current need. Convergence, DALI, DMX and LEDs In the meantime pure theatrical lighting control had moved down its own evolutionary path and developed its own protocols; the most used of which is the DMX512. (See Sections 5 and 6.) This protocol was developed to allow theatres to buy stage lighting from multiple vendors and link it all to the ever more complex show control desks that delivered the lighting (and other) effects on cue. As a result the DMX512 protocol is a highly robust and dynamic control method. In a way two branches had become three; i.e. energy saving, scene setting and show control. The arrival of LEDs onto the commercial lighting market has now brought the third way into the convergence of lighting control systems. LEDs came first to the theatre and early luminaires were all developed with DMX interfaces. As a consequence many of the evolved products moving into the commercial market continued to support this technology. As LED fixtures have become viable as commercial lighting solutions, the protocols from building lighting control systems have been adopted. DALI and IP (internet protocol) interfaces are to be found in both LED luminaires and drivers. www.thelia.org.uk Integration and networks The evolution of lighting control systems has involved many proprietary as well as open protocols in creating networks. With these diverse communication methods the question of integration to wider building management systems has been considered over the years. The subject of integration is discussed in the technology section alongside the various network protocols and interfacing options. Conclusion Lighting controls today are now developing along a more flexible, but integrated path, with the idea that all the control needs of any lighting application can be met by a single system.
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