What is the protection for IPBD? 

1 Answer

Answer :

Generator – GT overall differential protection.  

Related questions

Description : What are the tests to be carried during PM checks of IPBD?  

Last Answer : a) Physical inspection of bus for any spark or overheating or discoloration. b) Physical inspection of copper braided flexibles for discoloration. c) Physical inspection of inspection window gaskets, seal off ... Tan-delta test of IPBD m) IR value measurement n) Cleanliness checks entire IPBD. 

Description : What are the torque settings used in IPBD connection?

Last Answer : M12 (Nut bolt) 4506 100 kg-cm or 55 NM M16 (Nut bolt) 9006 250 kg-cm or 80 NM M20 (Nut bolt) 18006300 kg-cm or 100 NM 

Description : What are the isolations required for working on IPBD/ Generator?

Last Answer : a. Generator field breaker open and tagged. b. GT breaker open and earth switch closed.  c. Barring gear motor stopped and tagged. d. Generator PT's isolated and tagged. e. CB 472 and CB 474 open ... 's are isolated and tagged. f. Before doing any work on brush gear 64F1 relay to be taken out. 

Description : What is use of hot air blower in IPBD?

Last Answer : To remove moisture and to prevent moisture condensation inside the duct at commissioning time or in long shutdown periods. 

Description : Why seal-off bushings are used in IPBD?  

Last Answer : To prevent interchange of air at different temperature and leakage of hydrogen or infiltration of dust into the bus duct. 

Description : Why aluminium bus bars are silver-plated in IPBD?

Last Answer : Aluminium bus bars are silver-plated at flexible connection to prevent the galvanic corrosion ant also for low contact resistance. 

Description : Why neoprene rubber bellows are used in IPBD?

Last Answer : Neoprene rubber bellows are used near the terminals of the equipment and also at building wall from indoor to outdoor area to allow thermal expansion and to minimise vibrations. 

Description : What are the salient features of IPBD?  

Last Answer : a. This for a vital link between generator, GT, UAT, SPPT, SET and neutral grounding transformer. b. The continuous enclosure operating at ground potential limits the leakage flux outside the enclosure ... maintenance is nil. j. Separate parts erected IPBD. Hence changing parts makes it easy. 

Description : Why flexible expansion joints are used in IPBD?

Last Answer : To cater thermal expansion and contraction due to heating and to eliminate mechanical vibrations to the equipment. 

Description : What is type of nut and bolts are used in IPBD?  

Last Answer : Non-magnetic stainless steel nut and bolts are used in IPBD to restrict magnetic effect at joints.  

Description : Why neoprene rubber bellows in generator IPBD?

Last Answer : Prevent vibrations transmitted from generator to IPBD.  

Description : Emulsifier protection is associated with: a) Grounding protection b) Dielectric strength protection of cables and conductors c) Lightning protection d) Fire protection

Last Answer : Ans: D

Description : Where automatic restart does not present a hazard after a power failure, Coast Guard Regulations (46 CFR) require motor controllers for auxiliaries vital to the propelling equipment to be provided ... overload protection B. low voltage protection C. low voltage release D. reverse current protection

Last Answer : Answer: C

Description : Which of the spaces listed is defined as a 'location requiring an exceptional degree of protection' when considering the installation of shipboard electrical equipment? A. Machinery space B. Chart room C. Console room D. Accommodation space

Last Answer : Answer: A

Description : The wiring diagram for the motor starting circuit shown in the illustration indicates ______________. EL-0007 A. resistance starting B. reduced voltage starting C. low voltage protection D. low voltage release

Last Answer : Answer: C

Description : Which of the following statements is true concerning the motor controller diagram shown in the illustration? EL-0023 A. Terminal 'T2' is hot only on high speed. B. Both indicating lights will be lit on ... high speed operation only. D. 'L2' is always connected to 'T2' whenever the motor is running.

Last Answer : Answer: D

Description : The purpose of the automatic bus transfer shown in the illustration is to ___________. EL-0014 A. stepdown voltage to the lighting distribution panel B. provide emergency power to ... emergency switchboard from the main switchboard D. provide overcurrent protection to the lighting distribution panel

Last Answer : Answer: B

Description : Component F in the illustrated device is for _________. EL-0033 A. short circut protection B. latching the trip unit closed after resetting the breaker C. overload protection D. providing a flexible connection between the input terminal G and the tripping unit E

Last Answer : Answer: C

Description : A fuse will 'blow' if _____________. A. an electric motor is stopped suddenly by opening a switch B. the flow of current to the protection device is reversed C. the electrical current exceeds the rated value of the fuse D. unequal resistors are connected in parallel

Last Answer : Answer: C

Description : Periodic testing of circuit breakers is necessary to assure that a correctly rated and properly installed unit _________________. A. can trip faster as it increases in age B. will continue to provide ... not exceed its interrupting capacity D. be able to withstand at least 125% of applied voltage

Last Answer : Answer: B

Description : The 'reset' contacts of the master switch shown in the illustration provides the winch controller with ___________. EL-0102 A. low voltage release B. overload protection C. low voltage protection D. high power factor correction

Last Answer : Answer: C

Description : The speed of a series wound winch motor is controlled by ____________. A. varying the voltage applied to the motor B. the weight of the load on the cargo boom C. overcurrent protection devices in the motor D. a hydraulic speed-limiting governor

Last Answer : Answer: A

Description : The circuit shown in the illustration represents a ________. EL-0090 A. battery charging circuit B. synchronous exciter C. depth sounding unit D. cathodic protection system

Last Answer : Answer: D

Description : 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

Last Answer : Answer: D

Description : Impressed current cathodic protection is used on vessels instead of _________________. A. fire alarm systems B. repeated painting C. sacrificial zincs D. vacuum tube degaussing systems

Last Answer : Answer: C

Description : In an impressed current cathodic protection system, the anode is ____________. A. connected to the hull and deteriorates with time B. insulated from the hull and does not waste away C. connected to the hull but does not waste away D. insulated from the hull but deteriorates with time

Last Answer : Answer: B

Description : The amount of current flow required for the cathodic protection of a vessel is dependent upon the _________. A. amount of bare steel surface B. speed of the ship through the water C. temperature of the water D. all of the above

Last Answer : Answer: D

Description : The purpose of a magnetic relay is to _____________. A. open a circuit only in the event of overload B. remotely open and close contacts C. provide overcurrent protection during starting D. relay voltages at increased power

Last Answer : Answer: B

Description : RC time constant characteristics, as shown in the illustration, are important in _____________. EL-0086 A. bridge rectifiers for alternator excitation B. timing and pulse shaping circuits C. transistor power amplifier biasing D. motor controller overload protection

Last Answer : Answer: B

Description : The purpose of a motor undervoltage protection device is to _____________. A. prevent high armature current when power is restored B. start the motor at a very low voltage C. trip the load off the motor in case of fire D. protect personnel from low voltage shocks

Last Answer : Answer: A

Description : The purpose of an impressed current cathodic protection system aboard ship is to _______________. A. prevent corrosion of the hull, propeller, rudder and line shafting B. neutralize the vessel's ... the presence of salt air D. maintain a minimum constant alternator load to prevent overheating

Last Answer : Answer: A

Description : The type of control circuit that will not permit automatic restarting after power is restored, following a power failure is called _____________. A. low voltage protection B. low voltage release C. overload lockout D. reduced voltage restart

Last Answer : Answer: A

Description : The type of feature afforded auxiliaries vital to the operation of propelling equipment, where automatic restart after a voltage failure would not create a hazard, is termed _____________. A. low voltage protection B. high amperage protection C. low voltage release D. high amperage release

Last Answer : Answer: C

Description : Fuses placed in series with a thermal trip-type circuit breaker are used for _____________. A. time-delay protection B. short-circuit protection C. short duration surge protection D. sustained overload protection

Last Answer : Answer: B

Description : The main difference between a motor control circuit containing low voltage protection and low voltage release is that the latter contains _____________. A. a magnetic operating coil B. normally open line contacts C. thermal-overload protection D. a momentary-contact start button

Last Answer : Answer: D

Description : A low-voltage protection circuit is used in electric motor starting equipment to _____________. A. trip circuit contactors when the motor overspeeds due to low voltage B. trip circuit ... voltage without manually resetting D. prevent the motor from restarting automatically on restoration of voltage

Last Answer : Answer: D

Description : Protection against sustained overloads occurring in molded-case circuit breakers is provided by a/an __________. A. overvoltage release B. thermal acting trip C. thermal overload relay D. current overload relay

Last Answer : Answer: B

Description : A molded-case circuit breaker provides protection against short circuits by using a/an ________________. A. electromagnet B. shading coil C. arc quencher D. burn away strip

Last Answer : Answer: A

Description : A molded-case breaker provides protection against short circuits by using a/an ____________. A. shading coil B. arc quencher C. electromagnet D. holding coil

Last Answer : Answer: C

Description : How the electrical power system protection is divided?

Last Answer : The overall system protection is divided into • Generator protection • Transformer protection • Busbar protection • Transmission line protection and • Feeder protection

Description : What are the different relays that employed for protection of apparatus and transmission lines?

Last Answer : Answer: The relays that are usually employed for protection of transmission lines include • Over current relay • Directional relay • Distance relay • Under Voltage relay • Under-frequency relay • Thermal relay • Differential relay • Phase sequence relays • pilot relays

Description : What parameters or technical particulars are important to be considered while designing protection scheme of the transformer?

Last Answer : 1.Network Diagram showing the position of the transformer in the system 2.kVA or MVA rating of the transformer 3.Fault Level at the transformer 4.Voltage Ratio 5.Winding Connections 6.Per Unit ... Oil Filled 11.Length and area of cross section of the connecting leads between CTs and Relay Panel

Description : How Transformer Protection provided for internal faults?

Last Answer : 1.Bucholz Relay (1st Stage Alarm and 2nd Stage Trip) 2.Sudden Pressure Relay (1st Stage Alarm and 2nd Stage Trip) 3.Pressure Relief Valve (1st Stage Alarm and 2nd Stage Trip) 4.Pressure Switch ... 8.Gas Temperature Indicator (Alarm) 9.Silicon Breather (Passive - no alarm) 10.Smoke Detector (Alarm)

Description : Explain differential protection?

Last Answer : Differential protection is based on the fact that any fault within an electrical equipment would cause the current entering it, to be different, from that leaving it. Thus, we can compare the two ... phase or both and issue a trip output if the difference exceeds a pre- determined set value.

Description : What are the problems in bus zone differential protection?

Last Answer : Large number of circuits, different current levels for different circuits for external faults. Saturation of CT cores due to dc component and ac component in short circuit currents. The saturation ... the bus makes circuit complicated. Setting of relays need a change with large load changes.

Description : What are the merits of carrier current protection?

Last Answer : Fast operation, auto re-closing possible, easy discrimination of simultaneous faults .

Description : Why busbar protection is needed?

Last Answer : (a) Fault level at busbar is high (b) The stability of the system is affected by the faults in the bus zone. (c) A fault in the bus bar causes interruption of supply to a large portion of the system network.