Онлайн-тестування: Test about Diesel Generator (CBT)

By connecting a pair of voltmeter probes across one phase of the incoming generator circuit breaker, and then adjust the generator speed until the voltmeter slowly fluctuates from zero to maximum. Connect the breaker when the voltmeter passes through zero.

It is not possible to synchronise generators without the synchronizing aids.

By off-loading the running generator to a minimum to avoid large “kicks” at connection. Adjust the incoming generator to a frequency slightly less than the running generator. The running generator will then “pull” the incoming generator into synchronism.

70 %.

50 %.

80 %.

90 %.

120°.

180°.

90°.

60°.

1 800 rpm.

1 200 rpm.

900 rpm.

At its highest when the flux is at its lowest.

At its highest when the flux is at its highest.

At its highest when the flux change/time factor is at its lowest.

1 pole.

2 poles.

3 poles.

0,8-0,9.

0,9-1,0.

0,6-0,7.

1 352 A.

1 310 A.

950 A.

Change the speed drop, so that the diesel engine no. 2 will take a relatively larger part of the load.

Manually adjust the load sharing by means of the Up/Down switches on the main switchboard, until the running-in period is completed.

Change the max load setting on the governor.

Increase the DG 1 and decrease the DG 2 by means of the governor control.

Increase the DG 2 and decrease DG 1 by means of the governor control switch.

Increase the magnetisation on DG 2 and decrease the magnetisation on DG 1.

0,8.

0,85.

0,9.

1 161,6 rpm, 58,08 Hz.

960 rpm, 48 Hz.

1200 rpm, 60 Hz.

The thyristor for one of the generators is broken.

Someone has adjusted the potmeter in the main switchboard. The result of this is that the imbalance will increase proportionally to the total load increase.

Loose connection or broken diode in one of the diode bridges. This will cause the regulator to increase the output to achieve UN = UG. The regulator can manage this at low loads, but a higher loads the capacity is not sufficient to compensate for the loss of one diode.

Generator frequency is to slow relative to main bus.

Generator frequency is to fast relative to main bus.

The voltage is wrong, but the frequency is correct.

440 kilo Ohm.

220 kilo Ohm.

600 kilo Ohm.

No requirement at all.

Dirty fuel oil filter on the diesel generator taking the smallest load.

Speed drop settings on the governors are not equalized.

The speed set points for the diesel generators are not equalized.

It will start/stop the generator sets in response to varying load.

It will start/stop the generator sets in response to fuel consumption.

It will start but never stop the generator sets in response to varying load.

It will stop but never start the generator sets in response to varying load.

On the main switchboard.

On the generator.

On the diesel engine.

On the circuit breaker.

Optimal, because this mode allows an increased load of the generators during manoeuvring.

Equal, because of the wider control range, which allows the low priority generator(s) to be connected at low loads.

Cyclic, because the risk of fouling of intake channels are eliminated, and because of this, the risks of reduced capacity of the generators are minimized.

Ohmic load.

Inductive load.

Capacitive load.

The Priority 1 generator will be first IN/first OUT.

The Priority 1 generator will be first IN/last OUT.

At Cyclic control mode the generators change Priority order.

When automatic frequency control is selected, the “follow-up” will parallel shift the speed drop until the generator frequency = nominal frequency.

The Power Management System can be considered as a back-up system for the main switchboard.

The Start/Stop request alarm activates and stops the diesel at low LO pressure.

Because it has fewer components, a brush/slip ring generator is preferred, because it minimizes the need for maintenance.

The electronic voltage regulator is installed as a back-up in case of breakdown of the primary current transformer.

For quick regulation at connection of large consumers, the load dependant primary winding produces an output corresponding to 120 % of nominal voltage.

The electronic voltage regulator will open the thyristor when more excitation current is necessary.

An engine room fan is considered an inductive load.

An electric heater is primarily a capacitive load.

When the load consists of ohmic, inductive and capacitive loads, there is no weakening of the main field since the loads will neutralize each other.

The bus frequency will then “pull” the incoming generator into synchronism.

Connection at 12 may result in a reverse power trip on the incoming generator.

Because of the time delay (the time from pressing the button until the breaker is connected).