Garmin G900X Installation And Maintenance Manual page 290

15.4.4 GDU Lighting Setup
15.4.4.1 Main Lighting Page
Through configuration settings on this main lighting page, G900X/G950 lighting can be setup and
adjusted to suit each installation/cockpit environment. Each GDU must be configured for individual
performance. The GMA 1347 and GCU 476 lighting is also controlled from this page. Audio panel
lighting is directly tied to display configuration, normally to the PFD (if the PFD fails, the MFD supplies
lighting information to the GMA). A default lighting configuration is included in the standard
G900X/G950 configuration. The following guidance can be used to adjust the lighting performance.
15.4.4.2 Display/Key Parameters
The following parameters apply to both display lighting and key/bezel lighting. The two are divided into
separate windows on screen as shown in Figure 15-32.
INPUT: Input level is provided from two photocells on the display (ambient light) or an external avionics
dimmer bus voltage. Range is between 0 and 99.99. The higher number indicates a corresponding
demand for a brighter display. Input level is shown on the graph as the 'x' (horizontal) axis, with a
vertical magenta line showing the current input value. The input value is only adjustable by varying the
amount of light reaching the photocell or by manipulating the appropriate aircraft dimmer bus, if
equipped.
BRIGHTNESS: Depicts actual brightness level of the display, shown on the graph as the 'y' (vertical)
axis with a horizontal yellow line. For any given condition, the brightness is determined by the
intersection of the input level and the lighting curve. Range is between 0.0 and 99.99.
SOURCE:
Selection
PHOTO
14V DC
28V DC
5V DC
Page 15-48 G900X/G950 Installation and Maintenance Manual – Software, Configuration, and Calibration
Revision D
Figure 15-32. Main Lighting Page
Description
Allows the input level to be controlled by ambient lighting sensed from the
display's photocells.
Input level is controlled by 14 VDC dimmer bus.
Input level is controlled by 28 VDC dimmer bus.
Input level is controlled by 5 VDC dimmer bus.
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