Practical Integrated Lighting Design with Daylight (Part 2) Rate of Switch-off Time Duration and Number of Switch on and Offs in Regard to Working Hours and a Practical Integrated Lighting Design Method

• Published in: Journal of the Illuminating Engineering Institute of Japan Vol. 62; no. 11; pp. 566 - 574
• Main Authors: Ohno, Haruyo, Itoh, Katsuzo, Satoh, Ryuji
• Format: Journal Article
• Language: Japanese
• Published: The Illuminating Engineering Institute of Japan 25.11.1978
• ISSN: 0019-2341; 2185-1506
• DOI: 10.2150/jieij1917.62.11_566

By using the cumulative occurrence rate curve of the horizontal plane illuminance E0 from an unobstructed hemisphere of sky, the rate of switch-off time duration can be estimated for a designated illuminance E, where switch on and offs occur too frequently. In practical integrated lighting design, however, the number of switch on and offs will have to be reduced. This is done by taking the designated illuminance width in stead of designated illuminance. Taking this into consideration, E0-cumulative occurrence rate and the number of switch on and offs are calculated once again from the original recorded data for each 10%, 20%and 30% illuminance width of designated E. Based on these results, a utilization technique for integrated lighting design is presented. For a typical office room, the lighting engineer can easily estimate the rate of switch-off time duration. This estimation is made using a chart which is a combination of E0-cumulative occurrence rate curves and daylight factor distribution curves in an office room.