Practical Power Cable Ampacity Analysis
Author: Velimir Lackovic
Cable ampacity studies calculate the current-carrying capacity (ampacity) of power cables in underground or above ground installations. This ampacity is determined by the maximum allowable conductor temperature. In turn, this temperature is dependent on the losses in the cable, both I2R and dielectric, and thermal coupling between heat-producing components and ambient temperature.
The ampacity calculations are extremely complex. This is due to many considerations, some examples of which are heat transfer through the cable insulation and sheath, and, in the case of underground installations, heat transfer to duct or soil as well as from duct bank to soil. Other considerations include the effects of losses caused by proximity and skin effects. In addition, depending on the installation, the cable-shielding system may introduce additional losses. The analysis involves the application of thermal equivalents of Ohm’s and Kirchoff’s laws to a thermal circuit.
Once you complete your course review, you need to take a multiple-choice quiz consisting of twenty-five (25) questions to earn 4 PDH credits
This course is intended to provide you with the following specific knowledge and skills:
- Heat flow process in underground cables
- Adjustments factors that affect cable current carrying capacities (ambient, thermal resistivity, grouping etc.)
- Calculation of permissible short circuit currents (adiabatic and non-adiabatic)
- Calculation of permissible voltage drop
- Effects of installation methods
- Computer solutions
- Practical examples
Download the Course to review and begin earning your PDH credits.
We provide technical courses for PDH credits that meet Board requirements for Professional Engineers, Geologists and Land Surveyors. This courses is guaranteed to be accepted in AK, AL, AR, FL, GA, IA, IL, ID, IN, KS, KY, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, SC, SD, TN, TX, UT, VA, VT, WI, WV, and WY. Before purchasing this course, please confirm that your state Board is listed above.