NEC Reference Library
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310.16: Conductor Ampacities
Allowable ampacities of insulated conductors rated up to and including 2000 volts, 60°C through 90°C, not more than three current-carrying conductors in raceway, cable, or earth.
250.66: Grounding Electrode Conductor (GEC)
Sizing Grounding Electrode Conductors for Alternating-Current Systems.
250.122: Equipment Grounding Conductor (EGC)
Minimum Size Equipment Grounding Conductors for Grounding Raceway and Equipment.
310.15(B)(1): Temp. Correction Factors
Ambient Temperature Correction Factors Based on 30°C (86°F).
310.15(C)(1): Adjustment Factors
Adjustment Factors for More Than Three Current-Carrying Conductors.
Ch 9 Table 8: Conductor Properties
Conductor properties including resistance and reactance for voltage drop calculations.
Ch 9 Table 4: Conduit Fill
Dimensions and Percent Fill of Conduit and Tubing (EMT Example).
314.16(A): Metal Box Fill
Maximum number of conductors permitted in various sizes of standard metal boxes.
314.16(B): Volume Allowances
Volume allowance required per conductor based on wire size.
250.102(C)(1): Bonding Jumper
Grounded Conductor, Main Bonding Jumper, and System Bonding Jumper Sizing.
300.5: Minimum Burial Depth
Minimum cover requirements (inches) for direct burial, conduit, and other wiring methods.
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