Star Lighting Traffic Krypton signal lamps are constructed for 8,000-10,000+ hours rated life in order to operate reliably with a minimal number of failures through at least 9-12 months. They are built to last that long to comply with the usual maintenance intervals for adjusting and cleaning signal apparatus and for 100% group replacement lamps.
Overall labor costs are the lowest when lamps are group-replaced at scheduled maintenance intervals. The number of individual lamp replacement trips is reduced when Star Lighting high reliability long life traffic lamps are used.
Traffic safety requirements make it mandatory to keep signal lamp outages as rare as technically possible, and to replace failed lamps immediately! Star Lighting traffic signal lamps meet these safety requirements because they are designed specifically for long life, durable construction and high beam brightness. Lamps are manufactured under strict quality standards to eliminate defects which lead to early burnouts. It is generally recognized by Traffic Department administrators and engineers that the most economic method if signal system operation consists of using specially constructed signal lamps of superior quality, thus reducing failures between scheduled maintenance periods.
Group replacing all lamps routinely is most economical when a comparison is made between the direct cost of the new lamp and the cost of sending a crew with truck and ladder between scheduled maintenance dates to replace a single burned out lamp.
The cost of maintaining traffic signal systems in good working order depends upon the allowable length of scheduled maintenance intervals. The reliability of reasonably up-to-date signal equipment is such that the group replacement intervals can be spaced 9-12 months. Under more favorable systems conditions, maintenance intervals may be even longer. Therefore, it is important that the traffic lamps be of such uniform quality and long-life rating that practically all lamps burn through the full group replacement interval and only a small percentage fail between these intervals.
Long Life Rating For Krypton Lamps
Why is it necessary that lamps for economic signal operation have long life ratings like 8,000-10,00+ hours, when, during a group replacement interval of 9-12 months, the lamps operate only 3,300 hours on the average? The answers related to the average percent of lamp failures in the life of incandescent lamps. In order to keep lamp failures at 2-5% of all lamps installed during 9-12 month interval, the average user-hour rating must be 6,000-8,000 hours. However, the actual percent of lamp failures may vary depending upon the conditions existing at the signal. Vibration from surface traffic, buses, cars, trucks, trains, severe weather conditions, etc. will increase the number of failures within the group replacement interval.
Star Lighting Products, 11350 Brookpark Road, Cleveland, OH 44130. Tel: 216-433-7500; Fax: 216-433-7506.