Page 98 - Apprentice Manual_Neat

S5-Q124.) The system in the figure below is what?

a.) Fuel pressure monitor
There is no fuel line in the figure.
b.) Exhaust gas temperature monitor
There is no exhaust stacks or components in the figure.
c.) *Electronic Speed Control system
Correct. Note the magnetic pick-up, the wires to the controller and wires from the controller to
the actuator with arm.
d.) Generator frequency monitor
The figure contains an actuator with arm. Monitors do not have actuators. They only have sensors to
monitor with.

S5-Q125.) Device B in the figure above is:

a.) Photo proximity switch
A photo proximity switch would not work well in a dirty environment like an engine. It must remain
clean so as to see the light beam.
b.) *Magnetic pick-up
Correct. Magnetic pick-ups are used with ferrous metal gears. When the gear tooth passes, it
generates a pulse. It does not matter if it is covered in grease or oil, it uses magnetism to detect,
not optics.
c.) Pneumatic sensor
Pneumatic sensors are not fast enough to detect rotational speeds of an engine.
d.) Magnetic speed controller
There is no such device used in power generation.

S5-Q126.) Device A in the figure above is:

a.) Governor
It is one component of an electronic governor system, but not the governor.
b.) *Actuator
Correct. This device is controlled by the controller and applies the appropriate force necessary
to correct errors detected by the magnetic pick-up.
c.) Regulator
It does not have any ability to regulate.
d.) Monitor
It has no sensing capability. It has an actuator arm.

EGSA Apprentice Certification Program Study Guide - Page 90