What are the problems in station operation due to grid under voltage?

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What are the problems in station operation due to grid under voltage?

asked Nov 17, 2021 by anonymous

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Description : What are the problems in station operation due to grid under frequency?

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Transformers are used onboard ships with AC generators to _____________. A. change frequency B. increase power output to modulating frequency controllers C. decrease power output to modulating frequency controllers D. permit higher voltage for electric motor operation and low voltage for lighting circuits

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Magnetic controller contacts may become welded together during operation due to _____________. A. an open coil B. low contact pressure C. excessive ambient temperature D. excessive magnetic gap

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What is located under the ribbon and just above the worksheet grid?

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Last Answer : Answer: B

The relative speed between the magnetic fields of stator and rotor under steady state operation is zero for a (A) dc machine. (B) 3 phase induction machine. (C) synchronous machine. (D) single phase induction machine.

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Last Answer : Answer: D

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Last Answer : Answer: D

A split-phase induction squirrel-cage motor will not come up to speed, even though the rated voltage, rated frequency, and rated load are applied. The suspected trouble could be due to _____________. A. a faulty centrifugal switch B. broken rotor bars C. worn bearings D. all of the above

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Last Answer : Answer: D

Which of the listed items will stop a motor due to a reduction in voltage and restart it when the voltage is restored to normal? A. Low voltage protection circuit B. Non-renewable link fuse C. Renewable link fuse D. Low voltage release circuit

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Last Answer : Answer: D

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Last Answer : Answer: D

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Last Answer : Answer: D

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Last Answer : Answer: C

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Description : Under which of the following conditions will a lead-acid battery be given a 'test discharge'? A. To determine its capacity. B. Whenever a cell cannot be brought within 10 points of full charge ... cells is found to have less than normal voltage after an equalizing charge. D. All of the above.

Last Answer : Answer: D

Which of the following actions must be carried out before a voltage tester can be used to test the three line fuses to a three-phase motor? A. The fuses must be removed from the circuit. B. The starter must be placed in the STOP position to stop the motor. C. The three line connections in the motor terminal box must be disconnected and tagged. D. Nothing need be done as long as the motor is running under a light load.

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Last Answer : Answer: B

Under normal conditions, the speed of a two-speed squirrel cage induction motor is changed by varying the ____________. A. frequency of the applied voltage B. resistance in the rotor circuit C. number of field poles D. amplitude of the applied voltage

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Last Answer : Answer: C

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Last Answer : Answer: C

A compound generator has a no-load voltage of 250 volts and a full-load voltage of 230 volts, and therefore, is considered to be _____________. A. flat compounded B. over compounded C. under compounded D. terminal compounded

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Why under voltage tripping of motor is incorporated in motor feeder breakers?

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Last Answer : The under voltage can occur in case of bus fault. If the motors are kept connected they will feed the fault which may cause the damage. Due to the back feeding from the motor the motor will slow down ... case pht motor will not rotate for the designed 3 minute period in case of bus under voltage).

What satellite subsystem monitors onboard conditions such as temperature and battery voltage and transmits this data back to a ground station for analysis? A. Communications subsystem B. AKM C. TTC D. Transponder

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anonymous · Answer 1 · 2021-11-17T09:22:26+0000

a) All the HT motors overloaded.

b) VAR load increases on generator leads to heating up of rotor

c) Stator current increases for same power export leads to stator over heating.

What are the problems in station operation due to grid under voltage?

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