E. Exterior lighting consists of navigation lights, landing lights, nose gear taxi lights, wing scanning lights, runway turnoff lights, and beacon (anticollision) lights. The controls for the exterior lighting are located along the lower edge of the forward overhead panels. Power for all the exterior lights is from circuit breaker panel P18-3.
F. Exit lights above entry doors and emergency exit lights above emergency escape hatches are automatically illuminated if all airplane power fails. Each light assembly contains two nickel-cadmium batteries which are trickle charged by transformer-rectifier units when the switch on the forward overhead panel is in the ARMED position. Some of the light assemblies are removable from their mount and can be used as portable lights.
500
33-00 Page 2 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. Nov 15/66
CONTROL CABIN LIGHTING - DESCRIPTION AND OPERATION
1. General (Fig. 1)
A. The control cabin lighting includes general cabin illumination and specific area lighting. Intensity or background variations provide contrast to achieve optimum visibility. Dome lights provide general control cabin illumination. The captain's and first officer's stations are illuminated by fluorescent and incandescent lights in the lightshield, above the main instrument panels, and by integral lights in the panel lightplates and instruments. The observer's stations are illuminated by the dome lights and the observers' reading lights. The fluorescent floodlamps in the lightshields provide high intensity lighting for use under adverse visibility.
B. The EXIT light at the left of the control cabin door is controlled from the forward overhead panel and is normally switched to the ARMED position during flight. Illumination is then automatic in event of complete power failure (Ref 33-51-0, Emergency Lights).
2. Lightplates and Instrument Lights (Fig. 2)
A. Lighting is supplied from behind the surface of the pilots' panels and most of the instruments with small incandescent lamps. The lamps operate on 5 volts. Each lightplate of the pilots' panels contains two or more of the small lamps. This keeps sufficient lighting of the lightplate if only some of the lamps come on. If the lighting becomes too dim, then you must replace the lightplate. To use a lightplate again, you must first send it to the shop for lamp replacement. Instructions for lamp replacement are in the vendor's manual.
B. The 28-volt ac transfer buses No. 1 and 2 supply power to variable transformer light controls. The variable transformers supply 0 to 28 volts ac to step-down autotransformers which supply 0 to 5 volts ac to the light circuits. The variable transformer light controls are located on or adjacent to the panel lights they control.
C. The 28-volt dc buses No. 1 and 2 supply power to rheostat light controls. The rheostats are combined with the captain's and first officer's main instrument panel light control autotransformers. The rheostats provide 0- to 5-volt dc power to the DME digital display lights. The 26-volt ac standby bus will provide 5-volt power to illuminate the standby instruments (airspeed indicator, altimeter, and horizon indicator) in event of power loss at the 28-volt ac transfer bus No. 1. When de-energized, relay R237 connects 5 volts ac to the lights from transformer T168. Relay R237 and transformer T168 are located in P42.
3. Lightshield (Fig. 3)
A. External background lighting for the pilots' main instrument panels is provided by three light assemblies located on the underside of the lightshield. Each light assembly contains fluorescent lamps. On some airplanes dimmable incandescent lamps are mounted with the fluorescent lamps. On other airplanes the fluorescent lamps are dimmable and no incandescent lamps are installed. A radio noise filter and the fluorescent light ballast are located on the lower nose compartment ceiling beneath the instrument panels. When installed, the dimmable incandescent lamps provide low intensity floodlighting of panels when desired and two additional automatic switch controlled incandescent lamps are mounted adjacent to the other lights to provide emergency floodlighting in event of power failure.
502
Jun 20/92 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 33-11-0 Page 1
Control Cabin Lighting Equipment Location 525
33-11-0 Figure 1 (Sheet 1) Feb 15/72
Page 2
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
H61697 T53366
503 Control Cabin Lighting Equipment Location
Oct 20/83 Figure 1 (Sheet 2) 33-11-0
Page 3
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：737 AMM 飞机维护手册 灯 LIGHTS(6)
