Online Engineering Continuing Education Courses

Test Method for Calculating the Energy Efficiency of Single Voltage External Ac-Dc and Ac-Ac Power Supplies

Quiz Questions:

1.	A ___________________ power supply provides one dc or ac output that is either at a fixed voltage or user selectable through a selector switch.

		Single voltage
		Battery

2.	Active mode refers to a condition in which the input of a power supply is connected to line voltage ac and the output is connected to a dc or ac load drawing a fraction of the power supply's nameplate power output greater than zero.

		True
		False

3.	DC power ratio is the ratio, expressed as a percentage, of the total real output power (dc or ac) produced by a power supply to the real input power (ac) required to produce it.

		True
		False

4.	What is UUT mean?

		Unit Under Test
		Under Unit Test
		Unit Under Temperature
		None of the above

5.	The ________________is the ratio of the active, or real, power (P) consumed in watts to the apparent power (S), drawn in volt-amperes (VA).

		True power factor
		Displacement

6.	What does THD stand for?

		Total Harmonic Distortion
		Test Harmonic Distortion
		Total Harmonic Displacement
		None of the above

7.	The total or apparent power (S) is the product of rms voltage and rms current (VA).

		True
		false

8.	____________________is the appropriate ac input voltage of the power supply as specified by the manufacturer on the label on the housing of the power supply.

		Nameplate input voltage
		Active power

9.	Efficiency shall be calculated by multiplying the UUT's measured active output power at a given load condition by the active ac input power measured at that load condition.

		True
		False

10.	The rms value, taken over one period, of the instantaneous power is called Active power.

		True
		False