Part of the insulation of practically all electrical machinery is in the form of organic compounds which contain some amount of ______________. A. asbestos B. water C. fibre D. plastic

1 Answer

Answer :

Answer: B

Related questions

Description : Moisture absorbed in the windings or condensed on the surface of electrical machinery insulation ________. A. is good for long term preserving since most insulation is organic and contains some amount B. ... D. reduces the amount of current supplied or drawn by the machine so horsepower is limited

Last Answer : Answer: B

Description : As part of a routine maintenance program for deck machinery, you should ___________. A. inspect electrical wiring and pushbutton switches for evidence of corrosion or burned insulation B. disassemble ... covers and ventilate as weather permits D. Check drum switch contact pressure every three months

Last Answer : Answer: A

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 : Electrical machinery insulation will break down more rapidly due to _________________. A. low loading of motors and generators B. frequent megger testing C. high temperatures and vibration D. high operating frequencies

Last Answer : Answer: C

Description : When you are making a high potential test on a piece of repaired electrical machinery, a rise in leakage current indicates ____________. A. good insulation B. bad insulation C. high insulation power factor D. a high slot discharge factor

Last Answer : Answer: B

Description : Grounds occurring in electrical machinery as a result of insulation failure may result from _____________. A. deterioration through extended use B. excessive heat C. extended periods of vibration D. all of the above

Last Answer : Answer: D

Description : Which of the following statements is/are true regarding requirements for receptacle outlets aboard vessels? A. Each receptacle outlet operating at 100 volts or more must have a grounding pole. B. Outlets ... machinery with a portable light having a 50 foot flexible cord. D. All of the above.

Last Answer : Answer: A

Description : Polyurethane cannot be used to make (A) Automobile cushion (B) Thermal insulation in refrigerator (C) Coating and adhesive (D) Fibre reinforced plastic (FRP)

Last Answer : (D) Fibre reinforced plastic (FRP)

Description : Which of the following types of insulation will begin to deteriorate FIRST as a result of the heat generated in the conductor it surrounds? A. Varnished cloth B. Rubber C. Silicon D. Asbestos

Last Answer : Answer: B

Description : Which of the following statements best describes the material known as varnished cambric? A. Felted asbestos sealed with varnish. B. Cotton cloth coated with insulating varnish. C. Rubber ... Paper impregnated with mineral oil, specially wrapped with nonmetallic tape, and coated with varnish.

Last Answer : Answer: B

Description : The insulation resistance of electric equipment and machinery should be tested for the lowest normal insulation values _____________. A. immediately after shutting down the machine B. every time the brush rigging is ... starting up the machine D. every 30 days whether the machine is in use or not

Last Answer : Answer: A

Description : Routine maintenance of dry-type transformers should include ______________. A. preventing the entrance of water from broken pipe lines steam lines B. keeping protective surfaces and insulating bushings free of ... debris C. periodic testing of insulation resistance with a megger D. all of the above

Last Answer : Answer: D

Description : __________ practically possess no elasticity. (A) Vulcanite or ebonite (B) Spandex fibre (C) Polysulphide rubber (D) Epoxy resin

Last Answer : (A) Vulcanite or ebonite

Description : Routine maintenance of a ship's service alternator should include ______________. A. changing the pedestal bearing insulation yearly B. megger testing of all rectifying diodes C. lubricating excitation slip rings D. periodic cleaning of the air filters or screens

Last Answer : Answer: D

Description : Before testing insulation with a megohmmeter, the windings of large machines should be grounded for about 15 minutes just prior to the test as the ______________. A. insulation may be damaged ... number of leakage paths D. larger machines may acquire a charge of static electricity during operation

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 : The synthetic plastic used for making insulation cover in electrical wires is ________. a ) Bakelite b)melamine c)Polyvinyl Chloride d)Poly styrene

Last Answer : c)Polyvinyl Chloride

Description : For LV applications (below 1 kV), ______________ cables are used. (A) Paper insulated. (B) Plastic. (C) Single core cables. (D) Oil filled.

Last Answer : Ans: C For low voltage applications single core cables are suitable.

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 : 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 : Plywood is made from (A) Common timber (B) Bamboo fibre (C) Teak wood only (D) Asbestos sheets

Last Answer : Answer: Option C

Description : The chemical used in breather is A. Asbestos fibre B. Silica sand C. Sodium chloride D. Silica gel

Last Answer : Silica gel

Description : In a three-phase electrical system, three ground detecting lamps are provided. If all three lamps REMAIN at half-brilliance when the ground detecting test switch is operated, ______________. A. there is a ... must be replaced C. there are no grounds present D. the light bulbs are of improper voltage

Last Answer : Answer: C

Description : If the bearings of an electrical generator are failing more frequently than expected and the lubricating oil is sludging then you should ______________. A. check the connections to the output leads B. ... replace the bearing with a sealed roller type D. replace the thrust bearing of the prime mover

Last Answer : Answer: B

Description : In actual applications, electrical connections to 'R1-R2' of figure 'A' and to 'R1-R2- R3' of figure 'B' shown in the illustration are made by ______________. EL-0092 A. soldered contacts B. spliced and taped connections C. slip rings and brushes D. solderless crimp-on connectors

Last Answer : Answer: C

Description : Electrical circuits are protected against overheating by means of a/an ______________. A. circuit breaker B. amplifier C. diode D. capacitor

Last Answer : Answer: A

Description : Where can I find some quality asbestos insulation?

Last Answer : Asbestos products are banned in the U. S.

Description : Is there really asbestos in insulation?

Last Answer : Currently it is illegal to add insulation to a home with more than a very small percentage of asbestos. Exposure to these small quantities of asbestos typically do not cause harm and are ... insulation that needs to be removed as these older forms of insulation do present certain health risks.

Description : How to Know If Your Home Has Asbestos Insulation?

Last Answer : Asbestos is now banned in most new products in the United States. Though it's excellent as an insulation material, disturbing asbestos fiber is hazardous and may lead to damage to the lungs which ... into the air, the homeowner will need to have it removed by an asbestos abatement professional.

Description : State the reasons that the Navy is getting away from the use of asbestos insulation.

Last Answer : Breathing asbestos fibers can cause lung disease and/or cancer

Description : Choose the incorrect statement pertaining to organic compounds (1) They have low melting and boiling points (2) They do not dissolve in water (3) They are not easily combustible (4) They contain mainly carbon and hydrogen

Last Answer : They are not easily combustible

Description : (3) They are not easily combustible Explanation: Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.

Last Answer : Which of the process is known as nitrification? (1) Reaction of Nitrogen Monoxide with oxygen to form nitric acid (2) Reaction of nitrogen dioxide with water to form nitric acid (3) Conversion of ammonia to nitrites (4) Conversion of nitrite to nitric oxide

Description : Ketones are organic compounds. Name the functional group that all ketone molecules contain.

Last Answer : ANSWER: CARBONYL GROUP pr C DOUBLE BOND O

Description : On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. To check this insulation with the machine assembled you should use a____________. A. millivolt meter and a jumper B. ohmmeter C. megohm meter D. high potential tester

Last Answer : Answer: A

Description : On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. To check this insulation with the machine assembled you should use a____________. A. ohmmeter with the ... C. megohm meter with the machine running D. voltmeter and ampmeter with the machine running

Last Answer : Answer: B

Description : Which of the following statements concerning electrical cables is correct? A. Where they pass through watertight bulkheads, they should be fitted with watertight stuffing boxes. B. Electric cable coverings should ... , or glued in place where nonmetallic insulation is used. D. All of the above.

Last Answer : Answer: A

Description : The removal of paint from electrical equipment, such as generators, should be cautiously undertaken because ____________. A. the mechanical shock of paint removal lessens the dielectric strength ... phase windings frequently become isolated from each other due to dust interference at the terminals

Last Answer : Answer: B

Description : Electrical failures in motors are caused by the breakdown of insulation, which may be caused by _____________. A. penetration of moisture B. accumulation of dirt C. overheating D. all of the above

Last Answer : Answer: D

Description : The greatest single cause of electrical failures is ______. A. the breakdown of insulation B. overcurrent C. high inductance D. too frequent testing

Last Answer : Answer: A

Description : Accidental grounds in a shipboard electrical system must be repaired as soon as possible as they will ____________. A. result in immediate power outages B. damage circuit breakers C. appear on the ground detection system D. damage insulation and may cause outages

Last Answer : Answer: D

Description : When working on electrical circuits containing large capacitors, in addition to deenergizing the circuit, which of the listed precautions should also be taken? A. Keep all radio equipment ... capacitor insulation resistance. C. Ground the capacitor terminals. D. Check capacitor circuit polarity.

Last Answer : Answer: C

Description : Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings

Last Answer : Answer: D

Description : A galvanometer is an instrument used to measure ___________. A. thickness of galvanized metal B. resistance of electrical wiring insulation C. very small amounts of current or voltage D. quantity of galvans in an electric circuit

Last Answer : Answer: C

Description : Which of the listed groups of electrical insulation materials is best suited for the highest operating temperatures? A. impregnated cotton and silk B. unimpregnated paper and cotton C. pure glass and quartz D. mica and porcelain with bonding agents

Last Answer : Answer: C

Description : Which of the listed classes of electrical insulation is suited for the highest operating temperature? A. Class 90 (O) B. Class 105 (A) C. Class 130 (B) D. Class 180 (H)

Last Answer : Answer: D

Description : Electrical insulation is classed by the _____________. A. International Association of Electrical Manufacturers B. approximate operating voltage and current expected C. U.S. Coast Guard D. temperature stability of the manufacturing material(s)

Last Answer : Answer: D

Description : The life expectancy of electrical insulation, is approximately halved for an increased operating temperature of _______________. A. 10°C B. 25°C C. 50°C D. 100°C

Last Answer : Answer: A

Description : The operator of electrical motors should keep a constant check on the loads they carry because _____________. A. low loads necessitate frequent insulation cleaning B. exceeding nameplate values shortens ... wasted if full loading is not utilized D. power factor correction methods are load dependent

Last Answer : Answer: B

Description : Cleaning of electrical insulation should be _____________. A. done every six months B. accomplished every 12 months C. determined by need and not the calendar D. performed whenever the electrician is not otherwise busy

Last Answer : Answer: C

Description : Copper is often used as an electrical conductor because it _______________. A. has high resistance at low temperatures B. has a highly polished surface C. is able to pass current with little opposition D. holds insulation together well

Last Answer : Answer: C