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S3-Q61.) Continuous rated generators would be found in which of the following applications?

a.) A hospital’s backup system
This is usually a standby system unless in a remote area without public utility.
b.) *A remote science station’s primary power
Correct. Many remote national parks and research facilities relay on continuous run
generators for all power needs. There are day-to-day operations that must occur
unencumbered by having to rely on small backup generators.
c.) Urban home use
Not economically practical. Most homes may have a backup or standby generator, but rely on public
utility for main power.
d.) Only where there were never great deviations in load
Continuous run generators can handle vast fluctuations in load. This would not be an issue.

S3-Q62.) What is the difference in inductive type generators and synchronous type generators?

a.) Inductive has the ability to compensate for power factor
Synchronous motor can compensate for power factor by over exciting the rotor, but inductive
generators do not have this capability.
b.) *Synchronous has the ability to produce a controlled voltage
Correct. Under varying load conditions, synchronous generators produce a more consistent
voltage even during changing levels of P.F.
c.) Inductive requires a slow prime mover such as hydro turbines and synchronous requires high
speed steam turbines
This is exactly the opposite. Synchronous generators are used with slow prime movers and inductive
on high speed applications.
d.) There is no real difference
Items A, B, and C explain some of the differences.

S3-Q63.) When rating a three phase generator, the manufacturer includes the following information: KW,
amps, volts, PF, and ________. What is missing?

a.) KVAR
Not required or known without the load
b.) *KVA
Correct. Everything three phase is rated for apparent power or KVA (the combination of
resistive and inductive loads).
c.) HP
HP is not necessary. HP is a function of watts and can be calculated (746W/HP).
d.) Frequency
Frequency in the U.S. is always assumed to be 60Hz. This may apply if using foreign made
generators not designed for use in the U.S.

EGSA Apprentice Certification Program Study Guide - Page 74