Conduit Fill Calculator - Southwire

Re3TM Conduit Fill Calculator Conduit fill is the percent of area inside the conduit taken up by the cable(s). Provides quick and easy results for the conduit fill percent, per NEC® guidelines.

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Calculate Your Conduit Fill Percentage

A great tool to help electricians, engineers and contractors answer the question, "What size conduit do I use per the NEC®?"

The app will calculate the conduit fill percentages and jam probability for multiple conductors per NEC® Guidelines. Simply enter the conduit type and size, then specify your conductors.

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Download If considering the use of Cable-In-Conduit (CIC) products, please contact Southwire at [email protected] for more details on cable constructions, compliance, and weight limitations.

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Close NEC UTILITY Calculate FILL SIZE Conduit Conduit type EMT PVC Sch 40 & HDPE PVC Sch 80 Flex FMC RMC (GRC) Flex LFMC Flex LFNC-B IMC SDR 9 SDR11 SDR 13.5 TC-7 Select conduit size Conductors Calculate + – Fill

Jamming is the wedging of three or more cables when pulled into a conduit. This usually occurs because of crossovers when the cables twist or are pulled around bends. The jam ratio is the ratio of the conduit inner diameter and the cable outside diameter. A five percent factor was used to account for the overall cross-section of conduit bends. Jam Probability is only computed where total number of wires is greater or equal to 3.

NUM_HERE Wire type Copper THHN Copper XHHW Copper RHH-USE Aluminum THHN Aluminum XHHW Aluminum RHH-USE Copper 2kV PV Wire Aluminum 2kV PV Wire Copper 2.4Kv XLP Copper 2.4Kv EPR LSZH Copper 2.4Kv EPR PVC Copper 5kV Airport Lighting Aluminum 5kv MV105 100% Aluminum 8kv MV105 Aluminum 5kv MV105 133% Aluminum 15Kv MV105 100% Aluminum 15Kv MV105 133% PVC Aluminum 25Kv MV105 100% Aluminum 25kv MV90 133% Aluminum 35kv MV90 100% Aluminum 35kv MV90 133% CU 5kV 115 mil EPR Tape PVC CU 15kV 220 mil EPR Tape PVC CU 25kV 320 mil EPR Tape PVC CU 35kV 420 mil EPR Tape PVC AL 5kV 115 mil EPR Tape PVC AL 15kV 220 mil EPR Tape PVC AL 25kV 320 mil EPR Tape PVC AL 35kV 420 mil EPR Tape PVC User - Defined Size

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