View all text of Subjgrp 243 [§ 183.410 - § 183.460]

§ 183.425 - Conductors: General.

(a) Each conductor must be insulated, stranded copper.

(b) Except for intermittent surges each conductor must not carry a current greater than that specified in Table 5 for the conductor's gauge and temperature rating.

(c) For conductors in engine spaces, amperages must be corrected by the appropriate correction factor in note 1 of Table 5.

(d) Each conductor in a multiconductor sheath must be at least a No. 18 AWG conductor.

(e) Each conductor installed separately must be at least a No. 16 AWG conductor.

(f) Each No. 18 AWG conductor in a multiconductor sheath may not extend out of the sheath more than 30 inches.

(g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary conductors and terminations that are in ignition systems; pigtails of less than seven inches of exposed length and cranking motor conductors.

Table 5—Allowable Amperage of Conductors

Conductor size (AWG) Temperature rating of conductor insulation 60 °C (140 °F) 75 °C (167 °F) 80 °C (176 °F) 90 °C (194 °F) 105 °C (221 °F) 125 °C (257 °F) 200 °C (392 °F) 1810101520202525 1615152025253035 1420202530354045 1225253540455055 1040405055607070 8556570708090100 68095100100120125135 4105125130135160170180 3120145150155180195210 2140170175180210225240 1165195210210245265280 0195230245245285305325 00225265285285330355370 000260310330330385410430 0000300360385385445475510 NOTES 1. See the following table:60 °C75 °C80 °C90 °C105 °C125 °C200 °C (140 °F)(167 °F)(176 °F)(194 °F)(221 °F)(257 °F)(392 °F) Temperature rating of conductor0.580.750.780.820.850.891.00 2. See the following table:CorrectionfactorNumber of current carrying conductors: 30.70 4 to 6.60 7 to 24.50 25 and above.40
[CGD 73-217, 42 FR 5944, Jan. 31, 1977; 42 FR 24739, May 16, 1977, as amended by CGD 81-092, 48 FR 55736, Dec. 15, 1983]