LED signal lamp

摘要

A light emitting diode (LED) signal lamp includes a lamp housing having at least one light opening, a power connection mounted on the lamp housing for connection to a power cable, a plurality of LEDs mounted within the lamp housing to shine through the at least one light opening when powered, and a control circuit for supplying electrical power to the plurality of LEDs via the power connection. The control circuit is configured to permit the LED signal lamp to safely, reliably and effectively interact with wayside control systems designed for incandescent signal lamps.

主权项

1. A light emitting diode (LED) signal lamp comprising:
a lamp housing having at least one light opening; a first power connection mounted on the lamp housing for connection to a first power cable; a first plurality of LEDs mounted within the lamp housing to shine through the at least one light opening when powered; and a first control circuit for supplying electrical power to the first plurality of LEDs via the first power connection; wherein the first control circuit includes a load resistor and is configured to automatically use the load resistor to measure a first cable resistance of the first power cable and control the supply of electrical power to the first plurality of LEDs based thereon; and wherein the first control circuit further includes a first memory connection, the first control circuit being further configured to monitor first lamp failure criteria and to open the first memory connection upon determining satisfaction of the first lamp failure criteria, opening of the first memory connection being effective to indicate failure of first lamp operational tests transmitted via the first power cable.