NEC Reference Library
Instant access to the National Electrical Code® reference tables. Integrated with Pro Tools for high-speed site calculations.
Grounded Conductor & Bonding Jumper
Standard sizing for grounded conductors, main bonding jumpers, and system bonding jumpers.
Equipment Grounding Conductor
Minimum size for equipment grounding conductors based on OCPD rating.
Grounding Electrode Conductor
Sizing requirements for grounding electrode conductors based on service entrance wire size.
Minimum Burial Depth
Minimum cover requirements for various wiring methods and installation locations.
Minimum Burial Depth
Comprehensive cover requirements for all wiring methods.
Ambient Temperature Correction
Correction factors for conductors in ambient temperatures other than 30°C (86°F).
Conductor Bundle Adjustment
Adjustment factors for more than three current-carrying conductors in a raceway or cable.
Allowable Ampacities
High-speed reference for common Copper and Aluminum wire sizes (60°C to 90°C).
Allowable Ampacities
The master NEC ampacity table for all insulated conductors and terminal temperature ratings.
Metal Box Fill
Maximum number of conductors permitted in standard metal boxes.
Volume Allowances
Volume required per conductor based on wire size for box fill calculations.
Conduit Fill Master
Internal diameter and available fill area for all standard conduit types.
Conductor Properties
Resistance, reactance, and physical dimensions for standard AWG wires.
PVC Schedule 40 Fill
Fill area and internal dimensions for Schedule 40 PVC conduit.
PVC Schedule 80 Fill
Fill area and internal dimensions for Schedule 80 PVC conduit.
Rigid Metal Conduit (RMC) Fill
Fill area and internal dimensions for RMC conduit.
Sourced directly from the National Electrical Code® (NFPA 70), ensuring the highest level of accuracy for field work.
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