NCCER Power Generation Maintenance Mechanic Assessment EXAM
MOSTLY TESTED COVERAGE AREAS
1. Basic Safety and Lockout/Tagout
2. Basic Rigging and Sling Tension
3. Fasteners, Anchors, and Flange Bolt-Up
4. Oxyfuel Cutting and Construction Drawings
5. Gaskets, Packing, and Mechanical Seals
6. Lubrication and Precision Measuring Tools
7. Bearings, Couplings, and Shaft Alignment
8. Pumps, Drivers, Valves, and Piping Practices
9. Steam Systems, Heat Exchangers, and Turbines
10. Vibration, Balancing, Hydraulics, and Fuel Handling Equipment
NCCER Power Generation Maintenance Mechanic Assessment EXAM
1. Before a maintenance mechanic begins work on a generator that may contain
hazardous electrical and mechanical energy, which procedure must be applied first to
, prevent unexpected startup?
A. Increase the generator load to verify operation
B. Apply lockout/tagout procedures to isolate all energy sources
C. Remove the cooling fan guard while the unit is running
D. Start the generator and record operating parameters
Answer: B
Lockout/tagout controls hazardous energy before maintenance begins . 2
Electrical, mechanical, hydraulic, pneumatic, thermal, and stored energy can cause
serious injury if equipment unexpectedly starts or releases energy . 2
Increasing load, running the unit, or removing guards during operation directly
exposes the mechanic to hazardous energy.
2. Which instrument is commonly used to measure electrical resistance when checking
wiring, coils, or heating elements for open circuits and short circuits?
A. Ammeter
B. Voltmeter
C. Ohmmeter
D. Frequency meter
,Answer: C
An ohmmeter measures resistance in ohms . 2
Resistance testing is useful for checking wiring, coils, heating elements, and other
electrical components for open circuits, excessive resistance, or short circuits . 2
The circuit should be de-energized before resistance measurements are taken . 2
An ammeter measures current, a voltmeter measures voltage, and a frequency meter
measures frequency.
3. Which condition is most likely to cause excessive vibration in rotating power-
generation equipment such as a motor-driven pump or fan?
A. Proper shaft alignment
B. Balanced rotating components
C. Misalignment between shaft centers
D. Correct lubrication of bearings
Answer: C
Shaft or coupling misalignment can create excessive radial and axial forces that
produce vibration, bearing wear, coupling damage, and premature component failure
. 2
, Alignment should be checked using appropriate precision methods and manufacturer
specifications . 2
Proper alignment, balanced components, and correct lubrication reduce vibration
rather than cause it.
4. Which component in a conventional generator converts mechanical rotation supplied
by the prime mover into electrical energy through electromagnetic induction?
A. Alternator
B. Thermostat
C. Heat exchanger
D. Governor
Answer: A
The alternator, or generator electrical section, converts mechanical rotation supplied
by the prime mover into electrical energy through electromagnetic induction . 10
The prime mover provides the mechanical input while the generator produces the
electrical output . 10
A thermostat controls temperature, a heat exchanger transfers heat, and a governor
controls prime mover speed.