content_image/574084.jpg
2. Current load is 10 amps. 

3. The voltage source is 115 volts from bus to equipment. 

4. The circuit has intermittent operation. 

Step 1—From the left scale, find the wire length of 200 feet under the 115V source column. 

Step 2—Follow the corresponding horizontal line to the right until it intersects the slanted line for the 10-amp load. 

Step 3—At this point, drop vertically to the bottom of the chart. The value falls between No. 16 and No. 14. Select the next larger size wire to the right—in this case, No. 14. This is the smallest size wire that can be used without exceeding the voltage drop limit expressed at the bottom of the left scale. 

## Wire Identification 

The proper identification of electrical wires and cables with their circuits and voltages is necessary to provide safety of operation, safety to maintenance personnel, and ease of maintenance. All wire used on aircraft must have its type identification imprinted along its length. It is common practice to follow this part number with the five digit/letter Commercial and Government Entity (CAGE) code identifying the wire manufacturer. You can identify the performance capabilities of existing installed wire you need to replace, and avoid the inadvertent use of a lower performance and unsuitable replacement wire. 

## Placement of Identification Markings 

Identification markings should be placed at each end of the wire and at 15-inch maximum intervals along the length of the wire. Wires less than 3 inches in length need not be 

identified. Wires 3 to 7 inches in length should be identified approximately at the center. Added identification marker sleeves should be located so that ties, clamps, or supporting devices need not be removed to read the identification. The wire identification code must be printed to read horizontally (from left to right) or vertically (from top to bottom). The two methods of marking wire or cable are as follows: 

1. Direct marking is accomplished by printing the cable’s outer covering. [Figure 9-124B] 

2. Indirect marking is accomplished by printing a heat- shrinkable sleeve and installing the printed sleeve on the wire or cables outer covering. Indirectly-marked wire or cable should be identified with printed sleeves at each end and at intervals not longer than 6 feet. [Figure 9-125]  The individual wires inside a cable should be identified within 3 inches of their termination. [Figure 9-124A] 

## Types of Wire Markings 

The preferred method is to mark directly on the wire without causing insulation degradation. Teflon-coated wires, shielded wiring, multiconductor cable, and thermocouple wires usually require special sleeves to carry identification marks. There are some special wire marking machines available that can be used to stamp directly on the type wires mentioned above. Whatever method of marking is used, the marking should be legible and the color should contrast with the wire insulation or sleeve. 

Several different methods can be used to mark directly on the wire: hot stamp marking, ink jet printers, and laser jet printers. [Figure 9-126] The hot stamp method can damage the insulation of a newer type of wire that utilizes thin 

<img src='content_image/574084.jpg'>

