L-109.pdf

INSTALLATION OF AIRPORT TRANSFORMER VAULT AND VAULT EQUIPMENT L-109-1

DIVISION 16

ITEM L-109 INSTALLATION OF VAULT EQUIPMENT

DESCRIPTION

109-1.1 This item shall consist of the furnishing of all vault equipment, wiring, electrical buses, cable, conduit, potheads, and grounding systems. This work shall also include the painting of equipment and conduit; the marking and labeling of equipment and the labeling or tagging of wires; the testing of the installation; and the furnishing of all incidentals necessary to place it in operating condition as a completed unit to the satisfaction of the COR.

EQUIPMENT AND MATERIALS

109-2.1 GENERAL.

a. Airport lighting equipment and materials covered by Federal Aviation

Administration (FAA) specifications shall have the prior approval of the FAA, and are listed in Advisory

Circular (AC) 150/5345-1, Approved Airport Equipment.

b. All other equipment and materials covered by other referenced specifications shall be subject to acceptance through manufacturer's certification of compliance with the applicable specification when requested by the COR.

109-2.2 ASBESTOS CEMENT DUCT. Asbestos cement duct and fittings shall be in accordance with

Fed. Spec. W-C-571.

109-2.3 RIGID STEEL CONDUIT. Rigid steel conduit and fittings shall be in accordance with

Underwriters Laboratories Standard 6 and 514.

109-2.4 HIGH-VOLTAGE BUS. High-voltage bus shall be standard weight 3/8-inch IPS copper tubing or it may be insulated copper cable of the size and voltage rating specified.

109-2.5 BUS CONNECTORS. Connectors shall be similar to Burndy Type NT (or equal) for copper tubing. Connectors for insulated bus cable shall be of the proper size and type for the service intended.

109-2.6 BUS SUPPORTS. Bus supports shall be similar to Westinghouse No. 527892 (or equal), insulated for 7,500 volts, single clamp type for 2-bolt flat mounting.

109-2.7 GROUND BUS. Ground bus shall be 1/8- x 3/4-inch copper bus bar.

109-2.8 GROUND RODS. Ground rods shall be copper or copper-clad of the length and diameter specified in the plans.

INSTALLATION OF AIRPORT TRANSFORMER VAULT AND VAULT EQUIPMENT L-109-2

109-2.9 POTHEADS. Potheads shall be similar to G&W Type N, Shape C (or equal), unless otherwise specified. Potheads shall be furnished with plain insulator bushings and conduit couplings. Potheads shall have a rating not less than the circuit voltage.

109-2.10 FAA-APPROVED EQUIPMENT. Certain items of airport lighting equipment installed in vaults are covered by individual FAA equipment specifications. The specifications are listed below:

AC 150/5345-7 Specification for L-824 Underground Electrical Cable for Airport Lighting

Circuits

AC 150/5345-10 Specification for Constant Current Regulators and Regulator Monitors

109-2.11 OTHER ELECTRICAL EQUIPMENT. Constant-current regulators, distribution transformers, oil switches, cutouts, relays, terminal blocks, transfer relays, circuit breakers, and all other regularly used commercial items of electrical equipment not covered by FAA equipment specifications shall conform to the applicable rulings and standards of the Institute of Electrical and Electronic Engineers or the National

Electrical Manufacturers Association. When specified, test reports from a testing laboratory indicating that the equipment meets the specifications shall be supplied. In all cases, equipment shall be new and a first-grade product. This equipment shall be supplied in the quantities required for the specific project and shall incorporate the electrical and mechanical characteristics specified in the proposal and plans.

109-2.12 WIRE. Wire in conduit rated up to 5,000 volts shall conform to AC 150/5345-7, Specification for

L-824 Underground Electrical Cables for Airport Lighting Circuits, for rubber insulated neoprene-covered wire, or Fed. Spec. J-C-30, Type RHW, for rubber insulated fibrous-covered wire. For ratings up to 600 volts, thermoplastic wire conforming to Fed. Spec. J-C-30, Types TW, THW, and THWN, shall be used.

The wires shall be of the type, size, number of conductors, and voltage shown in the plans or in the proposal.

a. Control Circuits. Wire shall be not less than No. 12 AWG and shall be insulated for 600 volts. If telephone control cable is specified, No. 19 AWG telephone cable conforming to the

United States Department of Agriculture, Rural Electrification Administration (REA) Bulletin 345-14 shall be used.

b. Power Circuits.

(1) 600 volts maximum--Wire shall be No. 6 AWG or larger and insulated for at least 600 volts.

(2) 3,000 volts maximum--Wire shall be No. 6 AWG or larger and insulated for at least 3,000 volts.

(3) Over 3,000 volts--Wire shall be No. 6 AWG or larger and insulated for at least the circuit voltage.

INSTALLATION OF AIRPORT TRANSFORMER VAULT AND VAULT EQUIPMENT L-109-3

CONSTRUCTION METHODS

INSTALLATION OF EQUIPMENT IN VAULT

109-3.1 GENERAL. The Contractor shall furnish, install, and connect all equipment, equipment accessories, conduit, cables, wires, buses, grounds, and support necessary to insure a complete and operable electrical distribution center for the airport lighting system as specified herein and shown in the plans.

The equipment installation and mounting shall comply with the requirements of the National Electrical

Code and local code agency having jurisdiction.

109-3.2 POWER SUPPLY EQUIPMENT. Transformers, regulators, booster transformers, and other power supply equipment items shall be furnished and installed at the location shown in the plans or as directed by the COR. The power supply equipment shall be set on steel ``H'' sections, ``I'' beams, channels, or concrete blocks to provide a minimum space of 1-1/2 inches between the equipment and the floor. The equipment shall be placed so as not to obstruct the oil-sampling plugs of the oil-filled units; and name-plates shall, so far as possible, not be obscured.

109-3.3 SWITCHGEAR AND PANELS. Oil switches, fused cutouts, relays, transfer switches, panels, panel boards, and other similar items shall be furnished and installed at the location shown in the plans or as directed by the COR. Wall or ceiling-mounted items shall be attached to the wall or ceiling with galvanized bolts of not less than 3/8-inch diameter engaging metal expansion shields or anchors in masonry or concrete vaults.

109-3.4 CABLE ENTRANCE AND HIGH-VOLTAGE BUS SYSTEM. Incoming underground cable from field circuits and supply circuits will be installed outside the walls of the transformer vault as a separate item under Item L-108. The Contractor installing the vault equipment shall bring the cables from the trench or duct through the entrance conduits into the vault and make the necessary electrical connections. For the incoming and outgoing high voltage load circuits, the Contractor shall furnish and install rigid metallic vi conduit risers, surmounted by potheads, from floor level to the level as shown in the plans.

The incoming high-voltage power supply service to the vault shall enter below the floor of the vault and shall rise from the floor level in a rigid metallic conduit riser, surmounted by a pothead, as described above. Using insulated high-voltage cable, the incoming power service shall be connected from the pothead to the oil-fused cutouts or to the specified disconnecting switch or equipment. From the oil-fused cutouts or disconnecting device, the insulated service conductors shall be connected to the overhead voltage bus system of the vault. The high-voltage bus system shall utilize the materials specified and shall be mounted and installed in accordance with the requirements of the National Electrical Code or the local code agency having jurisdiction.

109-3.5 WIRING AND CONNECTIONS. The Contractor shall make all necessary electrical connections in the vault in accordance with the wiring diagrams furnished and as directed by the COR. In wiring to the terminal blocks, the Contractor shall leave sufficient extra length on each control lead to make future

INSTALLATION OF AIRPORT TRANSFORMER VAULT AND VAULT EQUIPMENT L-109-4

changes in connections at the terminal block. This shall be accomplished by running each control lead the longest way around the box to the proper terminal. Leads shall be neatly laced in place.

109-3.6 MARKING AND LABELING. All equipment, control wires, terminal blocks, etc., shall be tagged, marked, or labeled as specified below:

a. Wire Identification. The Contractor shall furnish and install self-sticking wire labels or identifying tags on all control wires at the point where they connect to the control equipment or to the terminal blocks. Wire labels, if used, shall be of the self-sticking preprinted type and of the manufacturer's recommended size for the wire involved. Identification markings designated in the plans shall be followed. Tags, if used, shall be of fiber not less than 3/4-inch in diameter and not less than 1/32-inch thick. Identification markings designated in the plans shall be stamped on tags by means of small tool dies. Each tag shall be securely tied to the proper wire by a nonmetallic cord.

b. Labels. The Contractor shall stencil identifying labels on the cases of regulators, breakers, and distribution and control relay cases with white oil paint as designated by the COR. The letters and numerals shall be not less than 1 inch in height and shall be of proportionate width. The

Contractor shall also mark the correct circuit designations in accordance with the wiring diagram on the terminal marking strips, which are a part of each terminal block.

METHOD OF MEASUREMENT

109-4.1 The quantity of vault equipment to be paid for under this item shall consist of all equipment installed, connected, and accepted as a complete unit ready for operation.

BASIS OF PAYMENT

109-4.2 Payment will be made at the contract unit price for each completed and accepted vault equipment installation. This price shall be full compensation for furnishing all materials and for all preparation, assembly, and installation of these materials, and for all labor, equipment, tools, and incidentals necessary to complete the item.

Payment will be made under:

Item L-109-5.2 Installation of Airport Transformer Vault Equipment in Place--per unit

MATERIAL REQUIREMENTS

Fed.Spec.J-C-30 Cable and Wire, Electrical (Power, Fixed Installation)

Fed.Spec.W-C-571 Conduit and Fittings, Nonmetal, Rigid; (Asbestos-Cement or Fire-Clay

Cement), (For Electrical Purposes)

AC 150/5345-7 Specification for L-824 Underground Electrical Cable for Airport Lighting

Circuits

INSTALLATION OF AIRPORT TRANSFORMER VAULT AND VAULT EQUIPMENT L-109-5

AC 150/5345-10 Specification for Constant Current Regulators and Regulator Monitors

END OF ITEM L-109