Document UT-MT-0780_EN
Page 8 of 39
Edition 03/10/2015
Supersedes edition 03/11/2014
LED INSET THRESHOLD AND THRESHOLD WING BAR LIGHT
LRTH04
INSTRUCTION MANUAL FOR USE, INSTALLATION AND MAINTENANCE
1
GENERAL
L
RTH04
inset LED threshold light is high intensity, unidirectional, 12” steady
burning type.
These fixtures are intended for use as threshold and threshold wing bar, in order to
provide a visual aid to the moving aircraft.
LRTH04
lights are in compliance with ICAO Annex 14 Vol.1, FAA AC 150/5345-46
(Style 3), IEC TS 61827 (Style 4) and NATO-STANAG 3316.
The fixtures described in this manual are designed to be connected to series circuit,
replacing those equipped with incandescent lamps, fed through standard isolation
transformers connected to CCR with variable current from 2.8 A to 6.6 A.
Location of these fittings shall be in compliance with ICAO - Annex 14, STANAG 3316
and FAA
2
MAIN FEATURES
Each light assembly consists of a removable fixture and a shallow base receptacle.
The fixture is waterproof and designed to withstand aircraft impact and roll-over
loads without damage.
The beam toe-in is obtained inside the light unit through different positioning of the
light source. In this way all lights result mechanically identical and the shallow base
installation becomes very easy because no precise toe-in is required during civil
works.
Power consumption: 36 VA for Threshold – 73 VA for Threshold Wing Bar.
2.1
REMOVABLE LIGHT UNIT
The removable fixture mainly consists of a dome, an optical assembly, a power
supply/control board, and a lower cover.
2.1.1
Dome
The dome is made of treated drop-forged aluminium and includes two windows to
seat the prisms, complete with gaskets, kept in the proper position by means of a
mounting plate fixed with HSCS M5x12 screws. In correspondence of the windows,
the dome is outside provided with identification letters “A”.
The dome is provided with six through holes for fastening the light unit to the base.
It is also provided with two suitable slots, in opposite position, to make easy the
fixture removal by using two suitable lifting tools (available on request, P/N 332.4140
or 332.4230). As alternative, two screwdrivers can be used.
