Northern Airborne Technology LD12-002 - Manual (Page 4)

LD12-002 LED Dimmer
SM85 Installation and Operation Manual
Section 1 Rev: 1.00 Issue 1 Page 1-1
ENG-FORM: 800-0116.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
Section 1 Description
1.1 Introduction
Information in this section consists of product description, design features and specifications for the
LD12-002 LED Dimmer. All derivative product information will be contained in the applicable manual
supplement, which may be obtained from Northern Airborne Technology Ltd. as required.
Review all notes, warnings and cautions.
1.2 Purpose of Equipment
The LD12-002 is a remote mounted light dimmer module, designed for complicated annunciator
requirements in Loran / GPS systems. The unit is capable of controlling 12 independent LEDs with full
test function. In its basic mode of operation, the LD12-002 can be used as a bulk LED dimmer, outputting
up to 1 amp of current. The LD12-002 unit can be easily interfaced with all NAT RS-series remote switch
products used in Loran / GPS installations.
1.3 Features
Internal logic is provided to interface to both the floating LED connections of the PB08, and annunciators
triggered by a ground output. An adjustable LED dimmer is provided to drive twelve separate 28 Vdc/50
mA LED lines.
The dimmer may be operated in the preset mode (typically set in the 12-24 V range), or as an adjustable
dimmer via an external control. A single switch can be used to select day, night, and LED test functions.
The day operation mode also provides regulated 24 Vdc for all LEDs, to prevent early LED failure and
internal LED blackening from excessive voltage.
All interconnect and relay contacts are gold plated. Relays are sealed, high vibration rated (50 g shock),
dry nitrogen filled units.
Circuit boards are constructed of G10-FR (flame retardant) material, with solder masks, reflowed tin
plating, and environmental post-coating.
1.4 Specifications
1.4.1 Electrical Specifications
Input Power
+24.8 Vdc to +30 Vdc, +27.5 Vdc nominal (reverse and
over voltage protection)
Input Current 50 mA idle (2 A max.)
Inputs
Test Keyline Active low input. Grounding this pin will cause all LEDs
to illuminate at full brightness.