The photoelectric sensors is applicable to control the street lighting, passage lighting and doorway lighting automatically in accordance with the ambient lighting level. This product is designed with electronic circuits. Its quicker response with time delay of 3-10 seconds offers easy-to-test feature. Especially, model JL-404C provides a wide voltage range for customer applications under almost power supplies. Further, a preset 3-10 seconds time-delay might avoid mis-operation due to spotlight or lightning during the night time. This product has been listed by UL Inc and is comply with the Standard for Non-industrial Photoelectric Switches for Lighting Control UL773A.