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Lighting Control for Demand Reduction Using ELI and Dencor EquipmentLighting control represents one of the largest opportunities for demand reduction to reduce utility costs. Controllable dimming ballasts from Electronic Lighting Incorporated and Dencor demand controllers have a unique synergy which helps customers save money by using lighting control. ELI Model LS3 Load Shedding Link The LS3 allows three contacts in a demand controller to select one of three different lighting levels. For example, lighting may be controlled to 90%, 70% and 54% power or to 90%, 82% and 70% power using the three contacts. The LS3 can control up to 1000 ballasts. Also, many LS3 Load Shedding Links may be connected in parallel to a single set of control contacts. Thus, if desired, a single set of three contacts can control 50, or more, LS3 modules and dim all the lighting in a 20 story building. Each LS3 can have its own selection of three dimming levels. This makes it easy to have dimming levels in areas close to windows greater than dimming levels in interior areas. If more than one control contact is closed the one specifying the most reduction will take precedence. Control System Interface The LS3 has 6 terminals; however, 3 are common. Thus a 4-conductor cable can be used to connect the LS3 (or multiple LS3s) to the contacts of a Dencor controller. Tie one terminal of each of the relays together in common. Measuring Demand The preferred method of measuring demand is by use of the KYZ pulses from the utility meter. These pulses are simply the contacts of a relay controlled by the rotation of the meter disk (or pseudodisk in electronic meters). The KYZ terminals are supplied by the utility, usually in a small enclosure. The main advantage of using KYZ pulses is that the controller is using the same information for control as the meter is using for billing purposes. If KYZ pulses are not available for some reason, current transformers can often be used. Control Systems Dencor has three series of controllers that may be used for lighting control. A brief overview is given. Dencor Series 300 Up to 24 relays are controlled by 16 priority levels. It can respond to
time-of-use demand rates including holidays and daylight saving time changes. Separate
on-peak, off-peak and critical demand levels may be set. Each relay may be used for both
demand limiting and time control. Thus, reduced lighting can be specified at night for
office cleaning and lighting controlled by demand used in the daytime. The Series 300C
also stores demand and temperature data to evaluate building performance. It also allows
telephone control of setup and data collection. Thus, it is especially useful where a
number of building are to be monitored from a single location. The flexibility and special
features of the 300C will make it the preferred control for all but the smallest
electronic lighting applications.
Dencor Series 200C Up to eight output relays are controlled by eight priority levels. It can respond to time-of-use demand rates including holidays and daylight saving time changes. Separate on-peak and off-peak demand levels may be set. One relay may be set to switch on time. The 200C has proven effective for demand control and can perform the basic functions needed for lighting control. The Data Display Station is included with the 200C-8E16 controller. To get started you need the 200C and arrange with your utility to obtain the KYZ pulse.
Dencor Model 30 The Model 30 is the smallest and lowest cost controller. It can have one or two output
control relays. It can be set so each relay operates on a different demand set point. No
time functions are available. The Model 30 included the D-30 data display station and the 12 Volt box mount control transformer for power.
Control Strategy The LS3 gradually changes the lighting from one level to the next over a period of time, usually about 3 minutes,. The gradual dimming makes the process virtually undetectable by the users. However, this creates a complication in the control strategy. The controller makes a decision to shed a load and then looks again in 30 seconds and checks to see what happened and determine if more control action is needed. In 30 seconds, the light load will only have dropped 1/5 of the demand it will eventually drop. It is a good idea to place other loads on priorities between the priority levels used for lighting reduction. Most buildings will have controllable loads, such as air conditioning, in addition to lighting. These loads can be placed on priority levels between lighting levels. For many installations, greater customer satisfaction and better demand control can b realized by using a second set of three contacts to control of the lighting. This makes it possible to start dimming lower priority lighting first and higher priority lighting when more demand reduction is needed. One of the big advantages of the Series 300C Energy Administration System is that the dynamic interaction of the loads is recorded making it much easier to find the optimal strategy for the utility rates, building equipment, and building use. New Opportunities Deregulation is creating many opportunities as customers become increasingly concerned about the future cost of power. We can help customers prepare for the future and improve operations in the present by providing the most effective combination of Electronic Lighting Incorporated lighting and Dencor Energy Administration Systems.
Commercial Systems Energy Control Load Research Irrigation Control Air Conditioner Cycling Heat and ETS Control Residential Demand Control Utility and Water Heater Control |
Central station software to setup and monitor the 300C is included with the
300C. To get started you need the 300C-L24 controller and a US Robotics 33.6 external
modem. You must also arrange for a KYZ pulse and a central station. The central station
should be at least a 150 MHz Pentium with 3GB hard drive and 16 Meg RAM.
