What is station Black out condition? 

1 Answer

Answer :

Simultaneous failures of class IV and class III supply is called Station Black out. In this condition class II power UPS will feed the necessary loads for a 30 minutes of duration. After that supplementary control room (SCR) 5 kVA UPS is used for secondary shut down system (SSS) ion chamber amplifier. 

Related questions

Description : What do you understand by station black out?

Last Answer : When class IV and class III power supply fails and DG’s cannot be started and also this condition prevails for 5 minutes then it is called station black out condition.  

Description : What propagation condition is usually indicated when a VHF signal is received from a station over 500 miles away? A. D-layer absorption B. Faraday rotation C. Tropospheric ducting D. Moonbounce

Last Answer : C. Tropospheric ducting

Description : What propagation condition is usually indicated when a VHF signal is received from a station over 5000 miles away? A. Moonbounce B. D-layer absorption C. Tropospheric ducting D. Faraday rotation

Last Answer : C. Tropospheric ducting

Description : An urgency message should include the following information: a. Name of station addressed, aircraft callsign, nature of urgency condition, intention of commander, position, level, heading b. Callsign, ... , callsign, present positin, level, ETA destination d. Captain's number, rank and name

Last Answer : a. Name of station addressed, aircraft callsign, nature of urgency condition, intention of commander, position, level, heading

Description : An urgency message should include the following information: a. Name of station addressed, aircraft callsign, nature of urgency condition, intention of commander, position, level, heading b. Callsign ... , callsign, present positin, level, ETA destination d. Captain's number, rank and name

Last Answer : a. Name of station addressed, aircraft callsign, nature of urgency condition, intention of commander, position, level, heading

Description : Suppose you are hurriedly rushing to your school in the morning. Meanwhile your eyes go across the road, where your student met an accident. What decision will you take under this critical condition ... want to take risk unnecessarily D) You are expressing the accident as an adventurous game

Last Answer : B) You reach the site, look after the student, after giving him first-aid, report to the police station and rush towards hospital

Description : Before any work on electrical or electronic equipment is performed, which of the following precautions should be carried out? A. De-energize the applicable switchboard bus. B. Bypass the interlocks. C. ... supply circuit breaker in the open position. D. Station a man at the circuit supply switch.

Last Answer : Answer: C

Description : Operation carried out in Thermal power station?

Last Answer : The water is obtained in the boiler and the coal is burnt so that steam is obtained this steam is allowed to hit the turbine; the turbine which is coupled with the generator generates the electricity

Description : What are the operation carried out in Thermal power station?

Last Answer : A: The water is obtained in the boiler and the coal is burnt so that steam is obtained this steam is allowed to hit the turbine, the turbine which is coupled with the generator generates the electricity

Description : List out the components of station output system. 

Last Answer : Main generator, Generator transformer, PT, CT, CVT, lightning arrestor, wave trap, main 220 kV bus, transfer bus, SF6 circuit breakers and isolators, line protection scheme, GT and Generator protection scheme, bus bar protection scheme etc.  

Description : Which of the following station is least efficient........ A.Nuclear power plant B.Diesel power station C.Thermal power station D.None of the above

Last Answer : Ans: C

Description : Coast Guard Regulations (46 CFR), require that an indicating light at the propulsion control station will operate if overloading or overheating occurs in a _______________. A. forced draft blower motor B. steering gear motor C. fuel pump motor D. condensate pump motor

Last Answer : Answer: B

Description : Sound powered telephone units 'I', 'II', and 'III' of the circuit shown in the illustration are for 'station numbers' _____________. EL-0093 A. 2, 4 and 6 B. 1, 2 and 3 C. 3, 5 and 8 D. 1, 2 and 6

Last Answer : Answer: D

Description : An overload in which of the listed motors will result in the illumination of an indicating light at the propulsion control station alarm panel? A. Fuel pump motor B. Steering motor C. Condensate pump motor D. Forced draft blower motor

Last Answer : Answer: B

Description : Sections 'I', 'II' and 'III' of the circuit shown in the illustration are 'station numbers' _____________. EL-0093 A. 2, 4 and 6 B. 1, 2 and 3 C. 3, 5 and 8 D. 1, 2 and 6

Last Answer : Answer: D

Description : If coil 'R1-R2' on the transmitter in figure 'A' shown in the illustration is turned 30 degrees clockwise, corresponding coil 'R1-R2' on the receiver should ____________. EL-0092 A. make coils 'S1 ... a higher voltage depending on the turns ratio D. align itself to the same position if free to move

Last Answer : Answer: D

Description : The pushbutton on the handset of a ship's sound-powered telephone must be depressed to ______________. A. talk then released to listen B. listen then released to talk C. both talk and listen D. ring the station being called

Last Answer : Answer: C

Description : Which of the following statements is correct concerning the circuits in a sound powered telephone system? A. The ringing circuit is composed of only one common wire to ground. B. The common ... connected to each station. D. The talking and calling circuits are electrically dependent upon each other.

Last Answer : Answer: B

Description : Factors on which material of station busbar depends?

Last Answer : Some of the factors on which station busbar depends are: Current Carrying capacity Short Circuit Stresses Establishing minimum electrical clearances

Description : List the factors to be considered while choosing a site for steam power station:

Last Answer : 1.Supply of fuel 2.Availability of water 3.Transportation facilities 4.Cost and type of land 5.Nearness to load centres 6.Distance from populated area

Description : What are the activities by which performance of the station will be judged? 

Last Answer : Activities of station by which performance is judged by public a. Capacity factor. b. Availability factor. c. Radiation release (gas and liquid effluents). d. Thermal release. e. Man-rem. f. ... l. The profit earned by the Plant. m. The quality and cleanliness in and around the Plant. 

Description : Why battery room should be located separately in a power station? 

Last Answer : Possibility of battery explosion Corrosive atmosphere by acid spray. Fire hazard. 

Description : What is the station ground resistance?

Last Answer : Less than 0.5 ohms.  

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

Last Answer : a) Turbine having under frequency limitation, house load happen if < 48 Hz b) Due to under frequency PHT flow reduces, therefore reactor power reduces, generator power reduces c) If frequency is ... Hz DG cannot be synchronised to grid, therefore DG kept on isolation running d) GT overfluxing. 

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

Last Answer : 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.

Description : A generating station has a maximum demand of 50 Mw, a load factor of 60%, a plant capacity factor of 45% and if the plant while running as per schedule, were fully loaded. The daily energy produced will be

Last Answer : A generating station has a maximum demand of 50 Mw, a load factor of 60%, a plant capacity factor of 45% and if the plant while running as per schedule, were fully loaded. The daily energy produced will be 720 MW.

Description : You are attempting to parallel two AC generators and the synchroscope pointer stops at a position other than 0°. If you close the circuit breaker at this moment _____________. A. the incoming ... hazardous condition will be created by the incoming machine being at a higher frequency than the bus

Last Answer : Answer: C

Description : One diode of a full-wave rectifier has burned out in a shorted condition. Therefore, the output will be ____________. A. zero B. a rectified half-wave C. a rectified full-wave D. equal to the AC input

Last Answer : Answer: D

Description : A full-wave rectifier has one diode burned out in an open condition, what will be the output characteristic of the device? A. Zero B. Half-wave rectified C. Full-wave rectified D. Equal to the AC input

Last Answer : Answer: B

Description : Action carried out by the relay and circuit breaker during fault condition?

Last Answer : Answer: After the relay sensing the fault condition, relay operates and close the trip coils. The effect of this will be circuit breaker operate to open the contacts.

Description : Junction breakdown occurs: a) With forward bias b) With reverse bias c) Under high temperature condition d) Because of excess heating of the diode

Last Answer : Ans: B

Description : If a DC motor runs hot, the cause may be _____________. A. high mica condition B. low ambient temperature C. clogged ventilation ducts D. an open in the shunt field

Last Answer : Answer: C

Description : In a three-phase electrical system, three ground detecting lamps are provided. One lamp goes dark and the others increase in brightness. When the test button is pushed, all lamps have equal illumination. You ... C. there are grounds on the lines with the bright lamps D. this is a normal condition

Last Answer : Answer: A

Description : Air gap readings should be taken on electrical generation machinery periodicly to _________. I. determine the need for cleaning II. check the condition of the bearings A. I only B. II only C. both I and II D. neither I or II

Last Answer : Answer: B

Description : Air gap readings for electrical generating equipment should be taken periodicly. This is to _______. I. determine the condition of the bearings II. prevent damage to the rotor and stator A. I only B. II only C. both I and II D. neither I or II

Last Answer : Answer: C

Description : If deck machinery is expected to be idle for an extended period of time you should____________. A. have electrical safety gloves available in case of electrical shock before running B. perform ... run at regular intervals to inusre correct operation and to renew the internal coating of lubrication

Last Answer : Answer: D

Description : Air gap readings should be taken periodicly on electrical generation equipment to __________. A. determine the amount of varnish that can be applied to correct insulation problems B. determine the ... field coil bolts and correct lateral adjustment of the field coils D. increase machine efficiency

Last Answer : Answer: B

Description : A flickering ground detection lamp on a DC system would indicate a _____________. A. multiple-ground condition in the distribution system B. ground in an armature coil of an operating machine C. ground in a motor accompanied with a short D. short between two adjacent bars of the generator commutator

Last Answer : Answer: B

Description : In a logic circuit the NOR and NAND gate functions ____________. A. must be accomplished with a common base transistor arrangement B. are available in diode form C. are exact opposites with the ... . have output conditions that are exact opposites to the output condition for OR and AND, respectively

Last Answer : Answer: D

Description : In a logic circuit, the NOT gate function _____________. A. does not alter a logical input B. serves to amplify a given signal level C. must be accomplished with a common collector transistor arrangement D. reverses an input logic condition

Last Answer : Answer: D

Description : When insulation failure produces a low resistance current path between two conductors, the resulting condition is known as ____________. A. an open B. a short circuit C. a ground D. a surge

Last Answer : Answer: B

Description : Which of the following procedures represents the best method to prevent the freezing of batteries continuously exposed to low temperatures? A. The battery caps should be removed. B. The battery cap ... in a fully charged condition. D. The battery should be disconnected from its charging source.

Last Answer : Answer: C

Description : The 'reset' contacts of the master switch shown in the illustration are ______________. EL-0102 A. closed only when the master switch is 'off' B. closed only when the master switch selects a 'run' condition C. opened separately by the winch operator D. opened when line voltage drops 10%

Last Answer : Answer: A

Description : Which of the following conditions indicates a short circuited capacitor when checking its condition with an ohmmeter? A. The capacitor shows charging, but the final resistance reading is appreciably less ... moves quickly to the low resistance side of the scale, then slowly recedes toward infinity.

Last Answer : Answer: B

Description : Which of the problems listed will occur if a lead-acid battery is allowed to remain in a discharged condition for a long period of time? A. The battery may be unable to accept a full charge ... . C. The concentrated sulfuric acid will attack the lead peroxide plates. D. The separators will harden.

Last Answer : Answer: A

Description : When a nickel-cadium battery begins gassing while connected to the battery charging circuit, you should _____________. A. do nothing as this is a normal condition when charging B. add distilled water ... to each cell to increase the specific gravity of the electrolyte D. decrease the charging rate

Last Answer : Answer: A

Description : When troubleshooting an electronic circuit, a cold solder joint can be located with the aid of an ohmmeter. Once the problem has been located, you should _________________. A. reheat the circuit in an ... a soldering tool and recheck with an ohmmeter D. do nothing as this is the normal condition

Last Answer : Answer: C

Description : One function of the movable cams in a drum-type motor controller is to _____________. A. regulate the speed of the motor B. maintain resistance contacts in clean condition C. insulate the operating handle D. limit the amount of load put on the motor

Last Answer : Answer: A