ITEM 684 TRAFFIC SIGNAL CABLES 684.1. Description. (1) (2) (3) (4) (a) (b)

[Pages:3]ITEM 684

TRAFFIC SIGNAL CABLES

684.1. Description. This Item shall govern for furnishing and installing traffic signal cables of the various sizes and types as shown on the plans.

684.2. Materials. All cables shall consist of two (2) or more individually insulated copper conductors. The insulation shall be polyethylene and rated for 600 volts. All cables shall be polyethylene jacketed.

All materials furnished by the Contractor shall be new.

(1) Type A cable shall be suitable for installation in underground conduit or use as an aerial cable supported by a messenger. The cable shall meet all the requirements of ISMA 20-1, which includes but is not limited to the requirements specified herein for Type A cable.

(2) Type B cable shall be an integral messenger cable for use in aerial installations as traffic signal interconnect cable. The cable shall meet all the requirements of IMSA 20-3, which includes but is not limited to the requirements specified herein for Type B cable.

(3) Type C cable shall be a two (2) conductor shielded cable for use as loop detector lead-in. The cable shall meet all the requirements of IMSA 50-2, which includes but is not limited to the requirements specified herein for Type C cable.

(4) The material for cable Types A and B shall be as follows:

(a) Unless otherwise shown on the plans, each conductor shall consist of seven (7) copper strands. The size and number of the conductors shall be as shown on the plans.

(b) Color coding of conductors and sequence for cables shall be in compliance with the following table. Base color shall be the insulation color. Tracers shall be colored stripes which are part of, or firmly adhered to, the insulation surface for the full length of the conductor.

CONDUCTOR COLOR AND SEQUENCE FOR CABLES

Conductor No.

Base Color

Tracer Color

1

Black

2

White

3

Red

4

Green

5

Orange

6

Blue

7

White

Black

8

Red

Black

9

Green

Black

10

Orange

Black

11

Blue

Black

12

Black

White

13

Red

White

14

Green

White

15

Blue

White

16

Black

Red

17

White

Red

18

Orange

Red

19

Blue

Red

20

Red

Green

21

Orange

Green

(c) Two (2) conductor cable shall be of the round twisted type with fillers used where necessary to form a round cable.

(d) In cables having more than two (2) conductors, individual conductors shall be laid up symmetrically in layers, with fillers used when necessary, to produce a uniform assembly of conductors with a firm compact cylindrical core.

(e) Fillers shall be of a non-metallic, moisture-resistant, non-wicking material.

(f) The conductor assembly shall be covered with a wrapping of a moisture-resistant tape applied to overlap at least 10 percent of the tape width.

(g) The taped conductor assembly shall be covered with a tight fitting black polyethylene jacket that is smooth, free from holes, splits, blisters and any other imperfections.

(h) Each cable shall clearly show the name of the manufacturer and the IMSA specification number applied at approximately two (2) foot intervals to the outer surface of the jacket by indent printing.

(5) Additional material requirements particular to Type B cable are:

(a) Cables consisting of five (5) or more conductors shall have a 0.25 inch nominal diameter messenger. The messenger shall be Class A galvanized Extra High Strength Steel Strand with three (3) or seven (7) wires.

(b) A solid strand messenger with 0.134 inch diameter may be used for cables with less than five (5) conductors.

(c) To provide corrosion protection, the messenger strand shall be coated and the interstices flooded with a rubber asphalt compound or equivalent.

(d) The integral messenger and conductors shall be enclosed in the jacket forming a cross section similar to a figure eight (8).

(6) The materials for Type C cable shall be as follows:

(a) Unless otherwise shown on the plans, No. 14 AWG insulated conductors with concentric stranding shall be provided. The insulation on one (1) of the two (2) conductors shall be black and the other shall be clear. The conductors within the cable shall have a minimum of two (2) twists per foot.

(b) The cable shall have 100 percent shield coverage utilizing aluminum bonded to a Mylar film. The drain wire shall be in continuous contact with the aluminum side of the shield material and shall be two (2) AWG sizes less than the conductor. The drain wire shall be stranded tinned copper.

(c) The jacket shall be black polyethylene.

(d) Each cable shall legibly show the name of the manufacturer and the IMSA specification number applied at approximately two (2) foot intervals on a tape under the outer jacket.

(7) Samples for establishing conformity to IMSA and this specification may be taken by the Engineer from each roll of each size of cable. The samples shall be a minimum of three (3) feet in length. Cable failing to meet IMSA requirements and this Item will be rejected and shall be replaced by the Contractor at the Contractor's expense.

684.3. Construction Methods.

(1) Installation of the cable shall be as shown on the plans. Each cable run in underground conduit shall have an extra length of five (5) feet coiled and left in each ground box.

(2) Splices will not be permitted except as shown on the plans, unless the Engineer approves each individual splice in writing. All allowed splices shall be watertight.

(3) Splices between Type C cable and loop detector wires shall be made only in the ground box near the loop it is servicing. Splices shall be soldered using non-corrosive solder. The drain wire of Type C cable shall be grounded to earth ground only at the controller or detector cabinet. The resistance from the drain wire to the ground rod shall be less than one (1) ohm.

(4) After installation of the cables and prior to any connection to the cables, the cables may be tested. Cable testing less than 50 megohms insulation resistance at 500 volts will be rejected.

684.4. Measurement. This Item will be measured by the linear foot of traffic signal cables except as shown below.

Measurement will not be made for cable inside signal heads and controllers and cable coiled in ground boxes, in pole bases and coiled on span wires.

This is a plans quantity measurement Item and the quantity to be paid for will be that quantity shown in the proposal and on the "Estimate and Quantity" sheet of the contract plans, except as may be modified by Article 9.8. If no adjustment of quantities is required, additional measurements or calculations will not be required.

684.5. Payment. The work performed and materials furnished in accordance with this Item and measured as provided under "Measurement" will be paid for at the unit price bid for "Traffic Signal Cables" of the various types and sizes specified. This price shall be full compensation for furnishing and installing all materials, and for all labor, tools, equipment and incidentals necessary to complete the work.

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