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S6-Q152.) Which item(s) could be used to compare the source rotation to the alternate source rotation?

a.) *Three phase motor or rotation meter
Correct. If the motor rotates in reverse on the generator from the direction of rotation on
utility power, a phase has been reversed. The rotation meter is designed to determine phase
rotation.
b.)VOM or amp clamp
These have no capability of determining phase rotation.
c.) Frequency meter
This had no means of detecting anything but frequency. Direction is not part of frequency.
d.) PF meter with an amp clamp
Power factor and current have nothing to do with phase rotation.

S6-Q153.) Which statement is true regarding routine maintenance?

a.) *All sources of power must be de-energized
Correct. For safety, the facility’s tag-out/lock-out procedures must be followed. In the event
procedures are not in place, consult NEC.(National Electric Code)
b.) Only the utility source of power must be de-energized
The generator could start or may be running causing injury or death.
c.) Always use the “one hand rule” when working on energized equipment
There is no real one hand rule. The types of voltages in industrial/commercial settings can travel
through one hand and arc out the other or travel through the legs to ground.
d.) Always use brass tool so as not to be attracted to any magnetic contactors
Brass still conducts. Tag-out/lock-out procedures should be employed.

S6-Q154.) The bypass isolation switch is used for what purpose?

a.) To test the load carrying capabilities of the contacts
Isolation would not test the load.
b.) *To test the automatic function without transferring the actual load
Correct. The generator is isolated and the switch tested without interrupting the load.
c.) To test for arcing when the load is switched from one source to another
Because there is no load involved, there would be little or no arcing.
d.) To isolate any potential ground faults on the secondary source
The secondary source should have its own ground fault detection equipment and the isolation is to
prevent connection to the load for testing.

S6-Q155.) Automatic Transfer Switch maintenance must be done to:

a.) Reduce fuel consumption
The switch will have nothing to do with fuel consumption. This is a function of KW produced.
b.) Completely eliminate failures from occurring
While this would be nice, it is not possible.
c.) *Improve the integrity of the emergency system
Correct. A properly maintained system will perform as it is designed to for many years
providing a favorable return on investment to its owners.
d.) Enable the generator to run
While this is true, even a poorly maintained system can run for a while.

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