
Explore electrical load calculations and design, including static and dynamic loads, derating factors, and cable sizing. Apply voltage drop and short-circuit calculations, select circuit breakers, and study building scenarios.
Explore electrical load calculations by distinguishing static and dynamic motor loads, determining circuit breaker currents and cable sizes, and applying category-specific tables for accurate design.
Learn how cable derating factors from installation in free air or underground affect current capacity, calculate the corrected current, and select cross sections using derating tables.
Compute voltage drop by determining corrected current and selecting cable cross sectional area. Use phase-aware formulas with resistance, reactance, cos phi, and sin phi to estimate the drop.
Learn to determine short circuit currents and select cross-sectional areas that withstand faults. Use copper and aluminum tables for PVC and xlpe insulation, and coordinate with circuit breakers.
Determine neutral and earthing cross sections according to load type; balanced three-phase loads use neutral half the phase size, while single-phase or harmonic loads require neutral equal to the phase.
Compare miniature circuit breakers, molded case circuit breakers, and air circuit breakers, highlighting pole configurations, rated currents, and braking capacities. Use these criteria in load calculations to select right breaker.
Master step-by-step static load calculations by determining three-phase and single-phase currents, evaluating kVA or kilowatts with power factor, and selecting breakers and cables, plus voltage drop and short-circuit checks.
Calculate load current for a 20 kW three-phase system, then select a 50 A circuit breaker and a 10 mm2 copper PVC multicore cable, verifying voltage drop and short-circuit rating.
Determine motor starting current by distinguishing static and dynamic loads, then use nameplate data and the kva code to calculate the starting current.
Calculate rated and starting currents for dynamic motor loads, then select circuit breakers and cable sizes using kilowatts, kVA, horsepower, efficiency, and power factor.
Calculate main cable and main circuit breaker by total rated current, total starting current, and thermal current, applying demand factor, then determine cross-section area and neutral/earthing needs.
Explore dynamic motor load calculations for a 380 V three-phase system, deriving currents, circuit breakers, and cable sizes for 5–16 hp motors, with derating and kVA codes.
Size the main breaker and cable for dynamic motor loads using demand and derating. Choose a 250 a mccb and 50 mm² phase conductors with 25 mm² neutral.
Learn step-by-step office building load calculations, including elevator, water pump, and chiller loads, to determine circuit breaker currents, cable sizes, and transformer and distribution board requirements.
Explain basement floor motor load calculations for two 7 hp elevators and a 30 kW water pump, computing currents, breakers, cables, and short-circuit coordination under 380 V 50 Hz.
Explain step-by-step static load calculations for ground, first, and second floors, determining rated currents, circuit breakers, thermal currents, and cable cross sections while considering derating and neutral and earthing conductors.
perform step-by-step roof floor load calculations for two 150 kw chillers and a 30 kw water pump, determining currents, breakers, and cable sizes.
Determine the required distribution transformer rating and main distribution board cables by calculating total building load, converting to kVA, and selecting an 800 kVA transformer with four 300 mm² phase cables.
Through my practical experience (19 years) in the field of electrical substations and working with various consulting offices in the design of medium voltage distribution networks for many important projects that require taking into account the accuracy in various electrical calculations, in addition to my obtaining a master’s degree in the engineering sciences in electrical power and machines engineering, entitled "Detection and Identification of Electrical Power Quality Problems using the advanced Artificial Intelligence Technique (LSTM). This course was prepared using the best engineering programs that link the academic/theoretical side with practical/reality in the High Voltage and Extra-High Voltage substations in addition to the Medium Voltage distribution networks.
This unique way of explanation and preparation of the course has been thought to suit all engineering and technical levels, starting from students of engineering universities and various technical institutes and even specialized engineers with high experience in the field of electrical power and distribution systems, especially the electrical contracting field, distribution networks and consulting offices.
This course was explained in a practical way based on the simple theoretical speech and attention to the practical explanation and reality pictures so that we can link the academic/theoretical study with what is actually present in the practical reality for the actual application after passing this course.
This course is closely related to electrical distribution systems and various contracting works. In this course, I offer the following:
* The meaning of Electrical Loads Calculations.
* The difference between dynamic or motors loads and static loads.
* The importance of the derating factors (D.F) in electrical loads calculations, and if we ignore these factors in our calculations, what will happen?
* In detail and step by step, I will explain, how to make the voltage drop (V.D) calculations for any cable.
* I will talk about, the short circuit (S.C) calculations for electrical power cables.
* I will explain how to choose the correct cross-section area (C.S.A) for the neutral cable and the earthing cable conductor.
* The difference between the Miniature C.B (MCB), Molded Case C.B (MCCB), and the Air C.B (ACB).
* In detail and step by step, how to make the correct and accurate calculations for any static load.
* I will give you an example of static load calculations and I will explain in detail and step by step, how to make the correct and accurate calculations for this load.
* I will explain how to know and calculate the starting current for any motor.
* I will explain in detail and step by step, how to make the correct and accurate calculations for any dynamic or motor loads.
* I will explain how to make correct calculations of the main cable and the main circuit breaker (C.B) for a group of individual motors or different loads.
* I will give you an example of dynamic or motor load calculations and I will explain in detail and step by step, how to make the correct and accurate calculations for these motors.
* I will give you a very important example of the office building calculations which consists of: the basement floor, ground floor, first floor, second floor, and roof floor with different loads of static loads and dynamic or motor loads like water pumps, chillers, and elevators.
* I will explain in detail and step by step:
- How to calculate the rated current of each circuit breaker (C.B) in ampere (A).
- How to calculate the cross-section area (C.S.A) of each cable in square-mm.
- How to calculate the rated current of the main circuit breaker (C.B) in ampere (A).
- How to calculate the cross-section area (C.S.A) of the main cable of each floor in square-mm.
* Finally, the last lecture is for the distribution transformer and the main distribution board calculations.