Operate Alternators, Generators. Test 1

What determines the power factor of an alternator when it is connected singularly to the switchboard?

The generated voltage
The excitation voltage
The load connected to the switchboard
Number of pairs of pole coils in the excitation winding

With no.1 and no.2 alternators running in parallel and the kW loads equally shared, one alternator is drawing much higher current than the other. What does this indicate?

Alternator frequencies are different and should be adjusted on the governor speed controllers
Alternators are out of phase and should be tripped and paralleled again
One alternator has lost one of its phases
The alternators are not generating the same voltages and should be adjusted on automatic voltage regulator rheostats

You are paralleling two alternators and the pointer of the synchronoscope slowly stops rotating and remains stopped in one position before the circuit breaker is closed. This would indicate:

The voltage of the incoming alternator is the same as that of the main switchboard
The incoming alternator is in phase with the switchboard, but the frequency is not the same
The frequency of the incoming alternator is the same as that of the main switchboard
The synchronoscope is not functioning properly and should be checked

With two alternators running in parallel, you wish to stop one. The first step is to:

Trip the main circuit breaker
Increase the frequency on the switchboard
Remove the load from the alternator to be stopped
Make sure the load is evenly shared

Before starting any maintenance on an electrical motor what should you do?

All of these.
Switch off the main switch and remove fuses for the motor.
Inform the duty engineer not to switch on the motor.
Hang a sign on the main switchboard to indicate that the motor should not be started.

You have just synchronized a second alternator onto the main switchboard, and want to equally share the load between the 'on' and incoming alternators. What would you do first?

Trip the circuit breaker of the incoming alternator and check the voltage and speed adjustments before trying again
Adjust voltage rheostat for the incoming alternator on the front of the switchboard
Raise the governor speed controller of the incoming alternator and reduce the governor speed controller of the alternator already on the switchboard
Lower the governor speed controller of the incoming alternator and increase the governor speed controller of the alternator already on the switchboard

With two alternators operating in parallel at 75% load capacity, one trips without any warning. What is the first action that should be taken?

Restart the tripped alternator immediately
Trip/stop all nonessential loads that are connected to the switchboard
Check the circuit breaker of the tripped alternator
Start and connect the emergency alternator

At which point do you engage the main circuit breaker of the incoming alternator when paralleling two alternators?

With the pointer of the synchronoscope at 0
With the pointer of the synchronoscope rotating fast and both synchronizing lamps flashing on and off
With the pointer of the synchronizer stopped at any position and both synchronizing lamps bright (on)
In none of the mentioned alternatives

Review Answers