A transformer is rated at 890 VA and has a primary voltage of 440 V and a secondary voltage of 180 V. Calculate the efficiency (in %) of the transformer operating at 0.60 rated load when the power factor is 0.75, the rated copper losses are 40 W and the rated iron losses are 12 W. Give your answer in percent. Answer: %

A transformer is rated at 890 VA and has a primary voltage of 440 V and a secondary voltage of 180 V. Calculate the efficiency (in %) of the transformer operating at 0.60 rated load when the power factor is 0.75, the rated copper losses are 40 W and the rated iron losses are 12 W. Give your answer in percent. Answer: %

EBK ELECTRICAL WIRING RESIDENTIAL

19th Edition

ISBN:9781337516549

Author:Simmons

Publisher:Simmons

Chapter24: Gas And Oil Central Heating Systems

Section: Chapter Questions

Problem 6R: The nameplate on a transformer will indicate whether or not it is a Class 2 transformer. (True)...

See similar textbooks

Similar questions

An open-delta three-phase transformer system has one transformer center-tapped to provide a neutral for single-phase voltages. If the voltage from line to center tap is 277 V, what is the high-leg voltage?
For an ideal transformer, the efficiency is (a) 0 (b) 100 (c) 50
What is the purpose of a transformer? Draw the symbols for a transformer.
A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when operated at rated load, 0.8 power factor lagging. This transformer is to be utilized as a 1440/1200-V step-down autotransformer in a power distribution system. (a) Find the permissible kVA rating of the autotransformer if the winding currents and voltages are not to exceed the ratings as a two-winding transformer. Assume an ideal transformer. (b) Determine the efficiency of the autotransformer with the kVA loading of part (a) and 0.8 power factor leading.
For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the rated voltage on the other winding? (a) Yes (b) No
The nameplate on a transformer will indicate whether or not it is a Class 2 transformer. (True) (False) (Circle the correct answer.)
All values of a transformer are proportional to its __________________ ___________________.
The symbol shown is a(n) a. iron core transformer. b. auto transformer. c. current transformer. d. air core transformer.
What are the advantages of correctly specifying a transformer most Suita ble for its application?
For the transformer in Problem 3.10. The open-circuit test with 11.5 kV applied results in a power input of 65 kW and a current of 30 A. Compute the values for GcandBm in siemens referred to the high-voltage winding. Compute the efficiency of the transformer for a load of 10 MW at 0.8 p.f. lagging at rated voltage.
Rework Problem 3.14 if the transformer is delivering rated load at rated secondary voltage and at (a) unity power factor, (b) 0.8 power factor leading. Compare the results with those of Problem 3.14. -
. A 220 / 400 V, 8.5 KVA, 50Hz single phase transformer has a full load copper loss of 104 W. Determine the Iron losses at an efficiency of 95.5 % at full load, 0.9 power factor. Also, find the efficiency of the transformer at 75% load at 0.7 power factor lagging. The Iron loss, Pi = Answer and unit for part 1 The efficiency of the transformer, %ηη =