Conductor Ampacity Based on the 2011 National …

1 2012 Schneider ElectricAll Rights ReservedRatings for 120/240 volts, 3-Wire, Single-Phase Dwelling Services See NEC Table (B)(7)These are permitted ratings for Dwelling Unit service and feeder conductors which carry the total load of the dwelling. NEC Conductors Minimum Ampacity and Size(A) Branch Circuit Not More Than 600 Volts.(1) General. Branch-circuit conductors shall have an Ampacity not less than the maximum load to be served. Where a branch circuit supplies continuous loads or any combination of continuous and noncontinuous loads, the minimum branch-circuit Conductor size, before the application of any adjustment or correction factors, shall have an allowable Ampacity not less than the noncontinuous load plus 125 percent of the continuous (amps)100 110125150175200225250300350400 Copper43211/02/03/04/0250 kcmil 350 kcmil 400 kcmilAluminum211/02/03/04/0 250 kcmil 300 kcmil 350 kcmil 500 kcmil 600 kcmilConductor Ampacity Based on the 2011 National Electrical Code Ampacity Based on NEC Table (B)(16) (Formerly Table ) Allowable Ampacities of Insulated Conductors Rated Up to and Including 2000 Volts, 60 Through 90 C (140 Through 194 F), Not More Than Three Current-Carrying Conductors in Raceway, Cable, or Earth (Directly Buried), Based on Ambient Temperature of 30 C (86 F)

2 *For conduit fill see 2011 NEC Annex Information on Temperature Ratings of Terminations to Equipment See NEC 110 .14(C). * Refer to (B)(2)(a) for the Ampacity correction factors where the ambient temperature is other than 30 C (86 F).** See Section (D) for Conductor overcurrent protection Rating of Conductor . [See Table (A).]SizeAWG orkcmil60 C (140 F)75 C (167 F)90 C (194 F)60 C (140 F)75 C (167 F)90 C (194 F)AWG or kcmilTy p e s T W, UFTy p e s RHW, THHW, THW, THWN, XHHW, USE, ZWTy p e s TBS, SA, SIS, FEP, FEPB, MI, RHH, RHW-2, THHN, THHW, THW-2, THWN-2, USE-2, XHH, XHHW, XHHW-2, ZW-2Ty p e s TW, UFTy p e s RH, RHW, THHW, THW, THWN, XHHW, USETy p e s TBS, SA, SIS, THHN, THHW, THW-2, THWN-2, RHH, RHW-2, USE-2, XHH, XHHW, XHHW-2, ZW-2 CopperAluminum or Copper-Clad Aluminum18 14 16 18 14**152025 12**20253015202512**10**30354025303510** 8405055354045 86556575405055 64708595556575 4385100115657585329511513075901002111013 01458510011511/01251501701001201351/02/0 1451751951151351502/03/01652002251301551 753/04/01952302601501802054/025021525529 0170205230250300240285320195230260300350 2603103502102502803504002803353802252703 0540050032038043026031035050060035042047 5285340385600700385460520315375425700750 4004755353203854357508004104905553303954 4580090043552058535542548090010004555456 1537544550010001250495590665405485545125 0150052562570543552058515001750545650735 455545615175020005556557504705606302000 Correction FactorsBased on NEC Table (B)(2)(a)[Formerly Table 310(16)] Ambient Temperature Correction Factors Based on 30 C (86 F)Adjustment Factors See NEC Table (B)(3)(a)

3 Where the number of current-carrying conductors in a raceway or cable exceeds three, the allowable ampacities shall be reduced as shown in the following table: ** Number of conductors is the total number of Conductor in the raceway or cable adjusted in accordance with (B)(5) and (6).NEC (A) Continuous and Noncontinuous LoadsWhere a branch-circuit supplies continuous loads or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus 125 percent of the continuous Protection of ConductorsConductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in , unless otherwise permitted or required in (A) through (G).NEC (D) Small ConductorsUnless specifically permitted in (E) or (G), the overcurrent protection shall not exceed that required by (D)(1) through (D)(7) after any correction factors for ambient temperature and number of conductors have been (A) Direct-Current Motor-Rectifier dc motors operating from a rectified power supply, the Conductor Ampacity on the input of the rectifier shall not be less than 125 percent of the rated input current to the rectifier.

4 For dc motors operating from a rectified single-phase power supply, the conductors between the field wiring output terminals of the rectifier and the motor shall have an Ampacity of not less than the following percentages of the motor full-load current rating:(1) Where a rectifier bridge of the single-phase, half-wave type is used, 190 percent.(2) Where a rectifier bridge of the single-phase, full-wave type is used, 150 Temperature ( C)Temperature Rating of ConductorAmbient Temperature ( F)60 C75 C90 C10 or or less11 5916 6821 7726 8631 9536 10441 11346 12251 13156 60 14061 65 14966 70 15871 75 16776 80 17681 85 185 Number of Conductors**Percent of Values in Table (B)(16) through Table (B)(19) as Adjusted for Ambient Temperature if Necessary4 through 6807 through 97010 through 205021 through 304531 through 404041 and Above35 This document provided by Barr-Thorp Electric Co., Inc. 800-473-9123