Selex Sistemi Integrati DMEL2 User Manual

1.INSTALLATION, INTEGR ATION AND CHECKOUT

1.1 Introduction

This section contains installation information for the independently located DME. If the DME is to be
collocated with VOR or ILS refer to the basic instructions in this section and to the installation instructions
for the VOR or ILS equipment. With respect to general requirements, a good VOR or ILS site will satisfy
the DME requirements as well. System performance must be verified by flight inspection. Figure 1-1
shows a typical DME site.

NOTE

After flight inspections and prior to use by pilots, it is mandatory that
the monitor be left in control of the facility and not in bypass.

1.2 Site Information

1.2.1 Site Selection

The signal radiated from the DME is affected by obstructions and terrain in the immediate vicinity of the
antenna and by obstructions and terrain within the service range of the station. An ideal site would be the
highest ground in the vicinity with level terrain, cleared of all objects for a radius of at least 3000 feet (915
meters), and with no obstructions extending above the horizontal plane of the antenna within the service
range of the station. In most localities, it is not possible to satisfy the ideal site requirements. Every effort
must be made to obtain the best site available. Although no absolute minimum requirements can be stated,
a site is normally acceptable if it meets the recommendations contained in the following paragraphs.

1.2.1.1 Terrain Features

The terrain should be level within a radius of 200 feet (61 meters). In a radius between 200 and 1000 feet
(61 and 305 meters), a downward slope is acceptable if (1) the rate of descent is not more than 4 feet in 100
feet (1.22 meters in 30.5 meters) and (2) contour lines are generally circular around the site. Beyond a
radius of 1000 feet (305 meters), terrain should be below the horizontal plane of the antenna.

1.2.1.2 Obstructions

There should be no structures within 750 feet (229 meters) of the antenna. Metallic structures should not
subtend vertical angles greater than 1.2 degrees as measured from the antenna. Wooden structures with
negligible metal content should not subtend vertical angles greater than 2.5 degrees as measured from the
antenna. Structures having considerable length (such as aircraft hangers or administration buildings)
should be situated lengthwise on a radial from the antenna. Single trees less than 35 feet (11 meters) high
may be tolerated beyond 750 feet. No group of trees or groves may be within 1000 feet. No overh ead
power or control lines are permissible within 750 feet of the antenna.

Figure 1-1 Typical DME Site

1.2.2 Shelter Requirements

The shelter location depends primarily on the maximum cable run allowed and on the desired location for
the DME antenna. An RF transmission line of 2" foamflex cable (with Type N connectors at each end),
one cable for the monitor antenna made up of 1/4" foamflex (with a Type N connector at one end and a
TNC male connector at the opposite end), and one AC cable for the OB Lite may be supplied with the
DME equipment. These cables are 35 feet long. When the requirements exceed 35 feet, company
engineering personnel can provide the necessary planning to determine the requirements.

The DME ground equipment is designed to operate continuously and unattended, but space must be
allocated for maintenance personnel and their equipment.

1.3 Unpacking and Repacking

The DME electronic subsystem is shipped unassembled. Only general precautions can be given because
the crating and unpacking depends upon destination and what optional equipment is included. Most items
are packed separately in individual containers; these are then grouped for crating. Each crate contains a
packing list which details what equipment is enclosed in the crate. Unpack the equipment and visually
inspect each item for accuracy and damage, but DO NOT REMOVE any ESD protective wrapping.
Report any damage immediately. After inspection, repack each item to prevent damage. During
installation, unpack items as they are needed.

1.3.1 Environmental Considerations
The environmental conditions must not exceed those listed in the Specifications of Table 1-1 Error!

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1.4 Input Power Requirement Summary
The requirements for input power must not exceed those listed in the Specification of Table 1-1 Error!

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1.5 Installation Procedures

1.5.1 Installation Tools and Test Equipment

Refer to Error! Reference source not found.for a list of test equipment and Table 1-1 for a list of special
tools required for installation.

Table 1-1 Special Tools Required for Installation

Description
Tube Cutter
File
Knife
2-1/4" Hole Saw
Assorted Screw Drivers and Wrenches
Thread Tape

1.5.2 Installation Kits

Refer to Table 1-2 for all component or modification kits required to install the DME station. Some kits
listed are optional equipment. Kits ending with “X” have many different varieties and will vary depending
on the site specific requirements. In all necessary cases installation drawings for each kit are provided with
the kit hardware.

Table 1-2 Component or Modification Kits Required to Install the DME

Part Number Description

470085-000X DME Tower Antenna Kit
470561-0001 DME Unidirectio nal GS Tower Mount Antenna Kit
470628-000X DME Battery Backup Kit, 35AHr
470622-0001 DME Accessory Kit
470627-0001 DME AC Power/Installation Kit
470291-000X DME OB Light Kit
470623-0001 Environmental Sensors Kit
470360-000X PMDT Kit

Table 1-3 Additional kits required to Install Shelter and Tower Grounding Systems

Part Number Description
470252-0002 Civil Install Kit, 45G Rohn Tower
470225-0001 Civil Install Kit, Shelter
470557-0001 Shelter Internal Grounding Kit

1.5.3 Shelter Foundation Installation

For shelters not supplied by SELEX Sistemi Integrati Inc., the manufacturer of the shelter will supply
drawings for the site engineer.

1.5.4 Shelter Installation

a. Use a crane and four nylon slings (20 feet long) to position the equipment shelter on the four concrete

piers.

b. Attach the shelter to the pier anchor bolts using appropriate hardware.

1.5.5 Tower Foundation and Tower Installation

A triangular steel tower is available for use as a support for the DM E antenna. Figure 1-2 shows the
installation details for this tower. Figure 1-3 illustrates the triangular tower adapter plate required to mount
the antenna to the DME tower.

1.5.6 Shelter and Tower Installation Grounding

a. Install ground rods and ground wire as detailed in Figure 1-2 and Figure 1-4.
b. Install the 470557 Shelter Internal Grounding Kit per the drawing provided with the kit.
c. Verify the shelter grounding plate, AC wiring, lightning protection, RF tower, and telephone

equipment all share a common grounding potential. The impedance between any of these items should
be below 10O.

1.5.7 Air Conditioner Installation

If a wall mounted air conditioner is supplied, install the air conditioner in the wall opening and secure it in
place using bracket su pplied. Apply silicon seal around air conditioner and wall opening to maintain a
weather tight seal.

Figure 1-2 Typical DME Tower Installation Diagram

Figure 1-3 Triangular Tower Adapter Plate

Figure 1-4 Typical DME Shelter and Tower Grounding Diagram

1.5.8 DME Cabinet Installation

a. Unpack the DME 19” rack system and stand upright inside the equipment shelter.
b. The rack can be located on an outside wall or in the center of the room; however the ventilation

louvers located on the left side of the cabinet must not be obstructed.

c. To level the rack use the adjustable feet then lock the feet positions using the jam nuts.
d. If desired the front and rear doors can easily be removed by sliding up the three hinge pins on the left

inside edge of each door. If the doors are removed be sure to replace them after installation.

e. Use #6 grounding wire provided in the AC Power/Installation Kit (Figure Error! Reference source

not found.) to connect from the DME grounding bus bar to the shelter grounding plate using the

shortest path possible.

NOTE: Do not install any modules in the rack until it is properly grounded.

1.5.9 Battery Backup Assembly Installation

a. Insure DME system AC and DC circuit breakers are in the OFF position.
b. Construct battery backup unit as detailed in Figure Error! Reference source not found. or per the

drawing provided with supplied battery backup kit.

c. Install the four twelve-volt batteries and connect batteries in series.