Reference information for the Wire Parameter Calculator at

http://circuitcalculator.com/wordpress/2007/09/20/wire-parameter-calculator/

 

Wire And Cable Derating Criteria From MIL-STD-975

 

Wire Size (AWG)

Derated Current (Amperes)

Single Wire

Bundled Wire or Cable

30

1.3

0.7

28

1.8

1.0

26

2.5

1.4

24

3.3

2.0

22

4.5

2.5

20

6.5

3.7

18

9.2

5.0

16

13.0

6.5

14

19.0

8.5

12

25.0

11.5

10

33.0

16.5

8

44.0

23.0

6

60.0

30.0

4

81.0

40.0

2

108.0

50.0

0

147.0

75.0

00

169.0

87.5

 

Notes:

1. Derated current ratings are based on an ambient temperature of 70C or less in a hard vacuum of 1E-6 torr.

2. The derated current ratings are for 200C rated wire, such as Teflon insulated (Type PTFE) wire, in a hard vacuum of 1E-6 torr.

a. For 150C wire, use 80% of value shown in Table 16.

b. For 135C wire, use 70% of value shown in Table 16.

c. For 105C wire, use 50% of value shown in Table 16.

3. The current rating for bundles or cables are based on bundles of 15 or more wires. For smaller bundles, the allowable current shall be determined by IBW = ISW x (29-N)/28 where N = number of wires, IBW = current, bundled wire and ISW = current, single wire.