MGVCL Exam Paper (30-07-2021 Shift 1)
A THHN conductor will have 75°C termination on one end and a 60/75°C termination on the other, which ampacity column will be used?
Conductor with 75 °C temperature rating must have ampacity from the 60°C column or the 75°C column. It is permissible to use the 75°C rating if the installed conductor is rated at least 75 °C. Because all of the connection points in this example have at least a 75°C rating, the conductor’s ampacity can be based on the 75°C column
A voltage dip is a short temporary drop in the voltage magnitude in the distribution or customer's electrical system. Common causes of voltage sags and under voltages are short circuits (faults) on the electric power system, motor starting, customer load additions and large load additions in the utility service area. Sags can cause computers and other sensitive equipment to malfunction or simply shut off.
Bus Type - Known Parameter - Unknown Parameter Load Bus -P, Q - V, phase angle Generator Bus - P, V (magnitude) - Q, Voltage phase angle Slack Bus Voltage - magnitude and phase angle - P, Q
Simple logic of reactance diagram is that simplified equivalent circuit of power system in which the various components of power system are represented by their reactance. The reactance diagram can be obtained from impedance diagram if all the resistive components are neglected. So, from figure each of the component is represented by its reactance.