Northern Airborne Technology LD12 - Manual (Page 12)

LD12 Lamp Dimmer Manual SM15 Rev. 4.00
Page 2-2 Nov 21, 2003
ENG-FORM: 805-0104.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.3.3 Notes
In order to minimize wiring, the unit should be located close to the annunciators it will be
dimming. It should not be mounted near hot air paths, as it needs to dissipate
substantial heat.
2.3.4
Cable and Wiring
Use Tefzel Mil-M-27500, Mil-M-22759 or Mil-M-81044 single conductor and shielded
wire with solder sleeves (for shield termination) to make the most compact and easy to
terminate interconnect. Follow the wiring diagrams provided in Section 2.4 as required.
Note that the hood is a "clamshell" hood and is installed after the wiring is complete.
Aircraft harnessing should permit the unit to be lowered from the panel for easy access
to all adjustments. DO NOT mount the unit until all adjustments have been carried out.
All wiring should be at least 22 AWG, except input power and ground connections which
should be 20 AWG. Ensure that the ground connection is clean and well secured and
that it shares no path with any electrically noisy aircraft accessories such as blowers,
turn and bank instruments or similar loads. To prevent system failure or inadequate
equipment protection, power to this system must be supplied from a separate breaker or
fuse (2 A) and not bundled to any other source.
2.3.5 Installation
Variations
The normal installation of the LD12-001 uses a single toggle switch for the pilot's
control. This selects the following modes:
DIM Night flying lamp levels. Can be adjusted either at the panel
or inside the LD12-001.
NORM Day flying lamp levels (full brightness).
TEST All lamps ON (full brightness). Tests functionality of all
lamps.
The switch is a SPDT center-off toggle, spring loaded in the TEST position so that it will
return to the normal position when released. Alternately, the DIM function can be
selected by a separate switch, or tied into another switch function, and the lamp test can
be activated by a momentary pushbutton switch.
The DIM position can also have a level control connected in series with the switch, to
permit local adjustment of the night flying lamp level. The switch may also be integral
with the level control to conserve panel space.