Power System

Module from the Electrical Engineering Curriculum curriculum.

Module 1 - Power System Design · Learning Objectives · 1. Read a one-line and identify voltage classes (LV <600V, MV 2.4-35kV, HV >35kV) · 2. Apply N+1 redundancy for critical process electrical loads · 3. Select voltage level by horsepower and motor loading · 4. Compute fault current contribution from utility, generators, and motors · 5. Coordinate protective devices (TCC curves) · Typical Voltage Selection by Motor Size

HP Range	Voltage	Reason	Starter	Wire Cost	Notes
<1	120V or 24V	Fractional HP	DOL	Cheap	Control circuits
1-50	208V or 480V	Utility service	DOL	Moderate	Standard small pumps
50-250	480V 3-phase	Economic	DOL or soft start	Moderate	Most refinery pumps
250-600	480V or 4.16kV	Starting kVA	DOL or reduced voltage	Higher	Above 250 HP consider MV
600-2500	4.16kV	MV for moderate loads	Reduced voltage	High	Large pumps, fans
2500-10000	4.16kV or 13.8kV	Utility-class MV	Reduced voltage	Very high	Compressors, boilers
>10000	13.8kV or higher	Efficient transmission	Reduced voltage	Highest	Large compressors

Source: Electrical_Engineering_Curriculum_v1.xlsx · Sheet: Power System

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