Marine Electrical Power Systems:
Electric Power Load Analysis (EPLA):
Cable, Bus Duct, and Bus Pipe Capacity Sizing

Last Update: May 6, 2026

Essential Questions

Essential Question Level of Thinking
What determines the required ampacity of cable, but duct, and bus pipe?
Understand
What are the factors that determine the ampacity of cables, bus duct, and bus pipe?
Understand
What are the impacts of non-fundamental frequency currents, installation details and ambient temperature on ampacity of cables, bus duct, and bus pipe?
Understand
How do bus pipe and bus duct installations differ from cable?
Understand
How can voltage drop calculations impact the size of cable, bus duct, and bus pipe?
Understand

Text Material

Cable, Bus Duct, and Bus Pipe Capacity Sizing ... (docx)

Presentation Material

Cable, Bus Duct, and Bus Pipe Capacity Sizing ... (pptx)

Images

I_20241116b Nuclear Ship Savannah Armored Cable

I_20220517a Cable ways on Emerald Princess

I_20260228d USS Alabama (BB 60) Cable

I_20260300b Sapphire Princess Cable Chafing

I_20251025a Insulated Bus Pipe Cross Section

Video Material

References

IEEE Std 45.1 IEEE Recommended Practice for Electrical Installations on Shipboard--Design

IEEE Std 45.8 IEEE Recommended Practice for Electrical Installations on Shipboard--Cable Systems

IEEE Std 1580 IEEE Recommended Practice for Marine Cable for Use on Shipboard and Fixed or Floating Facilities

MIL-DTL-917 Electric Power Equipment, Basic Requirements for

MIL-HDBK-299 Cable Comparison Handbook Data Pertaining to Electric Shipboard Cable

MIL-STD-1472 Human Engineering

DPC 310-1 Electric Power Load Analysis (EPLA) for Surface Ships

Doerry, Norbert H., "Impedance of Four-Conductor Cable," Naval Sea Systems Command, Technology Office (SEA 05T), Ser 05T / 011 of 2 Oct 2020. Available from DTIC AD1110943

Doerry, Norbert, "Shipboard power system limiting load flow and load flow analysis", IEEE ESTS 2025, Alexandria VA, August 5-8, 2025.

Doerry, Norbert, "Voltage Drop Calculations on Shipboard Power Systems", presented at 16th International Symposium on Practical Design of Ships and Other Floating Structures PRADS 2025, Ann Arbor, MI, USA, October 19th - 23rd 2025.


(C) Copyright 2024, 2026 Norbert Doerry

This work by Norbert Doerry is licensed under CC BY 4.0

Back to Shipboard Power System Fundamentals
Back to Marine Electrical Power Systems