OCEM MULTI ELECTRIC LTHE04 Instruction manual

Document UT-MT-0778_EN Page 1 of 39
Supersedes edition 02/03/2014
Via Farini, 6 –40124 Bologna - Italy
THIS COPY IS NOT SIGNED SINCE IT IS FILED AND DELIVERED BY MEANS OF THE AUTOMATIC KNOWLEDGE MANAGEMENT SYSTEM (IT CAN BE SIGNED ON REQUEST). THIS DOCUMENT AND THE DATA CONTAINED HERE IN, IS
PROPRIETARY PROPERTY AND SHALL NOT BE DUPLICATED, USED OR DISCLOSED –IN WHOLE OR IN PART –FOR ANY PURPOSE WITHOUT WRITTEN CONSENT OF OCEM.
LED INSET THRESHOLD/END LIGHT
LTHE04
INSTRUCTION MANUAL FOR USE, INSTALLATION
AND MAINTENANCE
Compiled by: Nicola Marabini
Approved by: Piero Scaramagli
N° Attachments: 1
Copy n°:
MULTI
ELECTRIC
group

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LIMITED PRODUCT WARRANTY
THE FOLLOWING WARRANTY IS EXCLUSIVE AND IN LIEU OF ALL OTHER WARRANTIES, WHETHER EXPRESS,
IMPLIED OR STATUTORY, INCLUDING, BUT NOT BY WAY OF LIMITATION, ANY WARRANTY OF
MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE.
OCEM - ENERGY TECHNOLOGY warrants to each original Buyer of Products manufactured by the Company
that such Products are at the time of delivery to the Buyer, free of material and workmanship defects,
provided that no warranty is made with respect to:
(a) any Product, which has been repaired or altered in such a way, in Company’s judgement, as to affect
the Product adversely;
(b) any Product which has, in Company’s judgement, been subject to negligence, accident or improper
storage;
(c) any Product which has not been operated and maintained in accordance with normal practice and in
conformity with recommendations and published specification of Company;
(d) the breaking of the warranty seals, if present, determines the immediate termination of the warranty;
and,
OCEM - ENERGY TECHNOLOGY’s obligation under this warranty is limited to use reasonable efforts to
repair or, at its option, replace, during normal working hours at the facility of the Company, any Product
which in its judgement proved not to be as warranted within the applicable warranty period. All costs of
transportation of Products claimed not to be warranted and of those repaired or replaced, to or from the
facility of the Company shall be borne by Purchaser. Company may require the return of any Product
claimed not to be as warranted to its facility, transportation prepaid by Purchaser, to establish a claim
under this warranty. The cost of labour for the installation of a repaired or replaced Product shall be
borne by Purchaser. Replacement parts provided under the terms of this warranty are warranted for the
remainder of the warranty period of the Products upon which they are installed to the same extent as if
such parts were original components thereof. Warranty services provided under the Agreement do not
assure uninterrupted operations of Products; Company does not assume any liability for damages caused
by any delays involving warranty service.
IMPORTANT: READ THIS DOCUMENT
Before proceeding to the operations of installation, commissioning, operation, maintenance or disposal,
carefully read the entire document.
SAFETY INFORMATION
Extreme caution should be exercised when working with this equipment; it is normally used or connected
to circuits that operate at dangerous voltages and can be fatal.
The following section contains important safety information that you must follow when installing and
using the apparatus.
Misuse of the equipment or lack of care in applying safety procedures and prescriptions specified in this
document, may result in a hazard.
Avoid contact with voltage or current sources.
For no reason the protections and the safety devices must be removed.

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OPERATION ON THE EQUIPMENT - SKILLS
Operation on the equipment and access to its internal parts shall be done by experienced personnel,
adequately trained and aware of the risks related to electricity and high voltages.
Safety rules shall be adopted when operating on the equipment, or on cables and other apparatus
connected to the it
DO NOT OPERATE ON ENERGIZED CIRCUITS
Do not carry out any operation on the converter or on apparatus connected to it when the circuits are
energized.
WHEN HANDLING AND SERVICING THIS EQUIPMENT, OBSERVE PRECAUTIONS FOR HIGH VOLTAGE
EQUIPMENT.
Before any access, inspection or intervention, be sure to have switched-off the unit, opened the main
circuit breaker and removed the supply to the unit (by opening the circuit breaker/switch on the
distribution board at the beginning of the supply line).
Then wait discharge time (at least 5 minutes), ground carefully the system, and check for voltage
presence before accessing..
REANIMATION
The maintenance staff must be aware of the risks related to electricity, criteria to prevent the risk of
electric shock and resuscitation techniques
CE MARK
This equipment complies with the requirements of European regulations for the CE mark.The
user has to respect all prescriptions reported in this document.
This equipment complies with the requirements of the EEC directives 2004/108/EEC and
2006/95/EEC with regard to “Electromagnetic Compatibility” and “Low Voltage Electrical
Apparatus” respectively.
OUT OF SERVICE
In case of dismantling, decommissioning, destruction, disposal, the user shall follow all the required
precautions for component and material elimination, according to local rules and applicable law.

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EDITIONS
Date
07/24/2013
First issue
02/03/2014
Deleted § “List of the recommended spare parts” and added relevant
attachment
11/03/2014
New address of the Company
Updated the P/N identification
REVISIONS
Index
Date
Description
Edited by
Approved by
LIST OF EFFECTIVE PAGES
From page 1 to page 39

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INDEX
LIMITED PRODUCT WARRANTY......................................................................................................... 2
SAFETY INFORMATION...................................................................................................................... 2
EDITIONS ........................................................................................................................................... 4
REVISIONS.......................................................................................................................................... 4
LIST OF EFFECTIVE PAGES.................................................................................................................. 4
INDEX................................................................................................................................................. 5
INDEX OF FIGURES............................................................................................................................. 6
LIST OF ATTACHMENTS ..................................................................................................................... 7
1GENERAL.........................................................................................................................8
2MAIN FEATURES .............................................................................................................8
2.1 REMOVABLE LIGHT UNIT................................................................................................ 8
2.1.1 Dome..................................................................................................................... 9
2.1.2 Optical Assembly................................................................................................... 9
2.1.3 Power Supply/Control Board .............................................................................. 10
2.1.4 Lower Cover ........................................................................................................ 10
2.2 SHALLOW BASE ............................................................................................................ 16
2.3 ELECTRONIC SECTION................................................................................................... 17
2.3.1 Current / current conversion circuit (patented)................................................. 17
2.3.2 LED command circuit .......................................................................................... 17
2.3.3 Control circuit ..................................................................................................... 18
2.4 ARCTIC KIT .................................................................................................................... 18
3INSTALLATION .............................................................................................................. 19
3.1 PAVEMENT BORING AND SAWCUTTING...................................................................... 19
3.1.1 Scheme of Light Configurations.......................................................................... 20
3.2 INSTALLING THE SHALLOW BASE ................................................................................. 21
3.3 INSTALLING THE LIGHT UNIT ON L-868 BASE, SIZE B ................................................... 25
3.4 SECONDARY WIRING .................................................................................................... 26
4MAINTENANCE ............................................................................................................. 27
4.1 MAINTENANCE PROGRAM........................................................................................... 27
4.1.1 Periodical Checks ................................................................................................ 27
4.1.2 Snowplow Operations......................................................................................... 28
4.2 REMOVING AND OPENING THE LIGHT UNIT FROM THE BASE .................................... 28
4.2.1 Removing the fixture .......................................................................................... 28
4.2.2 Opening the fixture............................................................................................. 28
4.2.3 Closing the fixture............................................................................................... 28
4.2.4 Leakage test ........................................................................................................ 29
4.2.5 Reinstalling the fixture........................................................................................ 29
4.3 PRIMS CLEANING.......................................................................................................... 30
4.3.1 Prism outside cleaning........................................................................................ 30
4.3.2 Prism inside cleaning .......................................................................................... 30

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4.4 PRISM REPLACEMENT .................................................................................................. 31
4.4.1 Removing the Prism ............................................................................................ 31
4.4.2 Installing the New Prism ..................................................................................... 31
4.5 LED MODULE REPLACEMENT ....................................................................................... 31
4.6 ELECTRONICS REPLACEMENT....................................................................................... 32
4.7 ARCTIC KIT REPLACEMENT ........................................................................................... 33
4.7.1 Thermostat.......................................................................................................... 33
4.7.2 Heater.................................................................................................................. 33
4.8 GASKETS........................................................................................................................ 34
4.8.1 Gasket examination ............................................................................................ 34
4.8.2 O-Ring replacement ............................................................................................ 35
4.9 CABLE LEAD WITH PLUG............................................................................................... 36
4.9.1 Removing the cable lead with plug..................................................................... 36
4.9.2 Installing the new cable lead with plug .............................................................. 36
4.10 PRESSURE VALVE .......................................................................................................... 36
4.11 CLEANING ..................................................................................................................... 37
4.12 MONITORING ............................................................................................................... 37
5TROUBLESHOOTING ..................................................................................................... 38
INDEX OF FIGURES
Figure 1 –8” Dome outside view ...................................................................................................... 9
Figure 2 –Lower Cover Outside View ............................................................................................. 11
Figure 3 –Lower Cover Inside View ................................................................................................ 11
Figure 4 –Wiring Diagram............................................................................................................... 12
Figure 5 –Exploded View ................................................................................................................ 13
Figure 6 –Part List........................................................................................................................... 14
Figure 7 - Complete P/N identification............................................................................................ 15
Figure 8 –Standard 12” shallow base............................................................................................. 16
Figure 9 –Pavement Boring, Sawcutting and Joint Intersection Details ........................................ 19
Figure 10 –Example of Light Unit Configuration ............................................................................ 20
Figure 11 –Gaskets for 12” shallow base ....................................................................................... 23
Figure 12 –12” shallow base for side or bottom ducts (method “B”)............................................ 23
Figure 13 –Shallow base installation details .................................................................................. 24
Figure 14 –Optical device (refer to the manual UT-MT-0485 for further information) ................ 24
Figure 15 –Gaskets for L-868 base ................................................................................................. 25
Figure 16 - Lower Cover Fixing Screws ............................................................................................ 29
Figure 17 - Lower Cover with Pressure Valve.................................................................................. 29
Figure 18 –Fixture Gaskets ............................................................................................................. 30
Figure 19 - Prism Cleaning............................................................................................................... 30
Figure 20 - Prism Replacement ....................................................................................................... 31
Figure 21 –LED Module Replacement ............................................................................................ 32
Figure 22 –Wiring diagrams for the heaters .................................................................................. 34
Figure 23–Fixture Gaskets .............................................................................................................. 35

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Figure 24 –Prism Gasket................................................................................................................. 35
Figure 25 - Cable Lead With Plug .................................................................................................... 36
Figure 26 - Lower Cover with Pressure Valve ................................................................................. 37
Figure 27 - Restoring the Monitoring Device .................................................................................. 38
LIST OF ATTACHMENTS
UC-PU-0274 - LIST OF THE RECOMMENDED SPARE PARTS

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1GENERAL
LTHE04 inset LED threshold/end light is high intensity, bidirectional or
unidirectional, 12” steady burning type.
These fixtures are intended for use as threshold/end, in order to provide a visual aid
to the moving aircraft.
LTHE04 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
2MAIN 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 fixture can be bidirectional type (bidirectional dome equipped with two (FAA) or
three (ICAO) LED modules, operating at the same time or independently) or
unidirectional type (unidirectional dome (FAA) equipped with only one green LED
module).
It is also possible to obtain an unidirectional light from a bidirectional dome choosing
the “S – Screened” option; this configuration includes a bidirectional dome mounting
only one LED module.
Power consumption for ICAO bidirectional fixture is 54 VA (1 or 2 plugs).
Power consumption for FAA bidirectional fixture is 40 VA (1 or 2 plugs), unidirectional
fixture is 22 VA (1 plug).
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.

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2.1.1 Dome
The dome is made of treated drop-forged aluminium and includes two (FAA) or three
(ICAO) 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” and “B”.
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.
A silicone O-Ring (separately supplied) has to be mounted outside around the dome,
to avoid dirt deposits between dome and shallow base.
1. Dome
2. Slot for dome removal
3. Letter “A” to identify the
beam
4. Through hole for light unit
fastening
Figure 1 –12” Dome outside view
2.1.2 Optical Assembly
The optical assembly consists of two (FAA) or three (ICAO) prisms (Figure 5 - n°13)
with relevant gaskets (Figure 5 - n°12) kept into the proper position by mounting
plate (Figure 5 - n°15) and two LED module (Figure 5 - n°7) with reflector (Figure 5 -
n°6). Unidirectional fixtures (FAA) mount only one prism and one LED module.
Each LED module consists of six LEDs mounted on a metal core PCB, coupled with the
support through thermo conductive material; the reflector is fixed to the support
assembly.
All the optical assembly parts are factory assembled; they may be field-replaced if
necessary.

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2.1.3 Power Supply/Control Board
The power supply/control board is encapsulated into waterproof and heat
conductive silicon resin.
The PCB powers and controls the LEDs so that the light output provided at every
current step from 2.8 A to 6.6 A is comparable to a traditional halogen lamp,
according to the requirements of FAA “Engineering Brief N°67” document.
2.1.4 Lower Cover
The lower cover consists of a treated aluminium casting; it is fastened to the dome
by means of six screws HSFH M5x10. Two O-Ring are provided between dome and
lower cover. The dome is equipped with a reference pin for its proper positioning.
The cover is provided with one or two threaded holes for cable entry and external
grounding screw with yellow-green cable lead, size 2.5 mm2, 0.460 m long, with male
faston terminal. A suitable valve is outside mounted for the leakage test.
Watertightness between fixture and shallow base is ensured by means of an O-Ring
(separately supplied) to be placed on the relevant shallow base groove.
The fixture is supplied with one or two cable lead with L-823 plug; they consist of
two single-pole teflon leads, size 2.1 mm2 (#14 AWG), 0.700 m long. The plug is in
compliance with FAA AC 150/5345-26 for very quick coupling with the receptacle
mounted on the shallow base.
If the light unit is equipped with one cable lead with plug, both the power
supply/control board sections will work simultaneously; if it is necessary to operate
independently the two power supply/control board sections, then two cable leads
with plug are necessary.
The fixture is 304 mm in diameter and 107 mm (+ 18.5 mm for plugs) high; the
protrusion above the ground is less than 6.35 mm.
An identification data label is externally applied over the lower cover (Figure 2 –n°2).
Moreover, to identify quickly the beam colour, the letters “A” and “B” of the dome in
front of the windows are painted in the same colour of the light beam.

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1. Lower cover
2. Identification label
3. Grounding cable hole
4. Letter “A” and “B” for
cable lead identification
5. Cable lead entry
Figure 2 –Lower Cover Outside View
The same colour painting is provided outside on the lower cover.
See “Complete P/N identification” figure for P/N information.
All hardware is made of stainless steel.
1. Cable lead with plug
2. Leak test valve
3. Letter “A” and “B” for
cable lead identification
Figure 3 –Lower Cover Inside View

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ICAO
POWER
SUPPLY
LEDLED
LED
LED
POWER
SUPPLY POWER SUPPLY
LEDLED
1 In 2 Out
2 In 2 Out
FAA
LEDLED
POWER
SUPPLY
LEDLED
POWER
SUPPLY
LED LED
POWER
SUPPLY POWER SUPPLY
1 In 1 Out
1 In 2 Out
2 In 2 Out
Figure 4 –Wiring Diagram

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1
2
3
4
5
6
7
8
9
10
11
1213
14
15
Figure 5 –Exploded View

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No. Description Qty
1 Dome....................................................................................................................1
2 O-Ring for dome (external)..................................................................................1
3 O-Ring for dome (internal)...................................................................................1
4 O-Ring for lower cover.........................................................................................1
5 Arctic kit heater................................................................................................ 1-2
6 Reflector with hardware .................................................................................. 2-3
7 LED module with accessories........................................................................... 2-3
8 Lower cover..........................................................................................................1
9 Valve for watertightness test...............................................................................1
10 FAA L-823 plug ................................................................................................. 1-2
11 Arctic kit thermostat ........................................................................................ 1-2
12 Prism gasket..................................................................................................... 2-3
13 Prism ................................................................................................................ 2-3
14 Prism holder gasket ......................................................................................... 2-3
15 Mounting plate ................................................................................................ 2-3
Figure 6 –Part List

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LTHE04 - F - GR - L - 2P - M - A
Basic P/N:
Compliance:
I = ICAO
F = FAA (L-850D)
Colour(Side A)/(Side B):
G = Green
R = Red
M = Blank (unidirectional dome - FAA only)*
Toe-in (threshold side)**:
L = Right
R = Left
S = Straight
Electrical System:
1P = One Plug
2P = Two Plugs
Monitoring:
0 = Without Monitoring
M = With Monitoring
Arctic Kit:
0 = Without Arctic Kit
A = With Arctic Kit
* The aperture not finished "M" will be always on side "B"
** The beams aiming is not field adjustable
CENTERLINE
THRESHOLD
"L" TOE-IN "R" TOE-IN
Threshold SIDE
Runway End SIDE
Threshold SIDE
Runway End SIDE
A
B
A
B
Figure 7 - Complete P/N identification

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2.2 SHALLOW BASE
The shallow base (Figure 8) consists of a treated aluminium casting containing an
electrical feed-thru system to connect the power cables, consisting of one or two
cable leads with receptacle incoming inside the base through one or two cable
glands. The cable lead with receptacle consists of two single-pole leads, size 2.5 mm2,
1.00 m long, with FAA L-823 receptacle.
The letters "A" and “B” are printed inside the base for cable leads identification.
The base is equipped with an internal grounding screw with yellow-green cable lead,
size 2.5 mm2, 0.250 m long, with female faston terminal for quick connection to the
corresponding of the fixture. An additional external grounding screw is provided
close to the cable entry.
The shallow base is designed for cementing in place by means of epoxy-resin in a hole
drilled in the pavement.
The fixture has to be fastened to the base by means of six hex cap screws, complete
with external silicon-coated lock-washer.
A gasket (separately supplied) must be placed between base and fixture for
watertightness (Figure 8 - n°9) placed in the relevant shallow base groove.
The 12” shallow base is 320 mm in diameter and 150 mm high.
On request, special bases without cable leads can be supplied, provided with holes
suitable for conduit connections.
Inside the base two suitable holders (Figure 8 - n°7) are provided to properly sustain
the secondary power cable, in case of this cable is inside incoming through a conduit.
1. Cable gland for cable entry
2. External grounding screw
3. Cable leads with socket
4. Internal grounding screw
5. Grounding cable with female
faston terminal
6. Letters “A” for cable lead
identification
7. Power cable holders
8. Threaded holes for fixture
fastening by bolts
9. O-Ring between fixture and base
Figure 8 –Standard 12” shallow base

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2.3 ELECTRONIC SECTION
The electronic section consists of the following circuits:
Current / current conversion circuit
LED command circuit
Control circuit
2.3.1 Current / current conversion circuit (patented)
This electronic section provide a conversion from the input current value (within
range from 2.8 A to 6.6 A) to the specified LED current value.
This conversion, performed in one transformation only, allows to achieve several
benefits:
minimize the power losses
significant increase of efficiency
high input power factor
independent form the CCR topology: the CCR may have any output current
waveform
no percentage of load dependent: the CCR can feed without any problem also
few lights in the series circuit
isolation transformers of smaller size can be used, respect to those used with the
equivalent fixtures equipped with halogen lamps
To meet the previous features, the conversion circuit is based on the MOSFET
technology. This circuit has been designed to withstand the several field stresses (like
withstand at elevated current peak) determinate by:
defective connections along the series circuit
sudden variations of the CCR power supply voltage; in many cases the CCRs don’t
provide suitable response time in order to compensate these variations
use of circuit selectors
The input circuit is protected against over-voltage, tested in accordance with the
requirements in FAA “Engineering Brief N°67” document.
2.3.2 LED command circuit
A PWM technique is used to command the LEDs. As known LEDs need to be supplied
with a constant current; therefore in order to vary the luminous emission with a
proper linearity is necessary the supply current will be applied at impulses. In other
words, the LED luminous output depends on the time of application (duty-cycle) of
constant current impulses.

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2.3.3 Control circuit
The main task of the control circuit is to assure the correct LED light emission
according to the series circuit current.
To perform this features, the circuit is provided with a current sensor that generate a
signal proportional to the series circuit current.
This signal is analyzed by a DSP which perform a RMS conversion of the input current.
The RMS conversion give a good accuracy with any input current waveform.
Other functions:
diagnostic, auxiliary voltage control and LED status control. In case of any LED
failure or relative power supply circuit failure, the electronic control circuit
commands the intervention of the monitoring device so that the secondary side
of the isolation transformer becomes open, like in the case of an incandescent
lamp failure. This features is essential when the monitoring option is required
events recording (not-volatile memory) for diagnostic purposes
PC operator interface through serial connection: this features allows to calibrate
the brightness depending on the current, to modify the emission curve, to read
the events occurred during the operating time
2.4 ARCTIC KIT
The optional arctic kit is in compliance with FAA “Engineering Brief N°67” document
and it prevents from the ice over the prisms area.
The arctic kit is connected in series to the PCB and it is consists of a thermostat (two
in case of fixture with double cable lead) and one or two heaters. It starts when the
dome temperature is less than about -1°C and turns-off when the dome temperature
reaches about 10°C.
Arctic kit consumption is less than 40 VA per plug.

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3INSTALLATION
3.1 PAVEMENT BORING AND SAWCUTTING
Drill each recess in pavement following the instruction in Figure 9.
Figure 9 –Pavement Boring, Sawcutting and Joint Intersection Details
Make sure the recess size and depth are maintained within the specified limits. All
surfaces of the recess must be clean and dry. If any of these surfaces is damp, it is
desirable that it be dried and blown clean with a compressed air blast. The recess
side walls must be perpendicular to the pavement surface. The bottom surface must
be flat or slightly concave to assure that the shallow base rest securely and in true
position. The recess can best be drilled using a diamond-faced core drill in a sturdy,
stable drill rig.
Mark on the pavement surface the aiming direction of the light by chalk, nails or
other devices.

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3.1.1 Scheme of Light Configurations
Figure 10 –Example of Light Unit Configuration