2 A 1000 kVA 11 kV/400 V ONAF cooled transformer works on a cycle of 3 hours heavy load and 21 hours light load. The peak load is 140 % which can only be maintained for 0.5 hours per hour of time constant. The average cooling air temperature is 25 °C and the oil temperature at the start of the peak load is 65 °C. Prepare a 24-hour loading schedule to include the maximum time the peak load can be maintained and the permissible loads that can be maintained for the remaining periods. Information: The thermal time constant for an ONAF transformer up to 12.5 kV is 3 and the relevant loading factors are given in the source document.

2 A 1000 kVA 11 kV/400 V ONAF cooled transformer works on a cycle of 3 hours heavy load and 21 hours light load. The peak load is 140 % which can only be maintained for 0.5 hours per hour of time constant. The average cooling air temperature is 25 °C and the oil temperature at the start of the peak load is 65 °C. Prepare a 24-hour loading schedule to include the maximum time the peak load can be maintained and the permissible loads that can be maintained for the remaining periods. Information: The thermal time constant for an ONAF transformer up to 12.5 kV is 3 and the relevant loading factors are given in the source document.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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