1-Phase Power Delivery Design ? LOAD B You are designing the power delivery system (cable selection) to a load that is connected to a single-phase 25kVA transformer. Between 8AM - 5PM the load is equal to 2kW, during which time the xfmr secondary voltage is 121V (point A). The load is 1.5kW the remaining times of the day, during which time the xfmr secondary voltage is 126V. The cable that runs between the xfmr and load will be 250ft. The available cables to install are listed in the table below. The voltage at point B can never be below 5% nominal (114V for 120V system) according to ANSI Std C84.1. Identify the cable to meet C84.1 and provide the most efficient power delivery method. Answer the questions below based upon your selection. Cable A Cable B Cable C Cable D Ohms/ft Ampacity 0.00016 14 0.00012 18 0.00008 22 0.00004 28 a) The voltage at point A utilized to determine your design b) The maximum current flowing to the load will be c) Which cable possesses the largest cross-sectional area d) What cable size should be selected to meet C84.1 requirements e) What cable size provides the most efficient power delivery method f) Based upon your cable selection, the minimum voltage at point B will be g) The max voltage drop across the cable will be between times h) The maximum power loss in the cable will be i) The maximum power demand of the load and cables will be

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.10P: A single-phase step-down transformer is rated 13MVA,66kV/11.5kV. With the 11.5 kV winding...