For an insulating material, dielectric strength and dielectric loss should be respectively high and low
Description : What is dielectric strength of an insulating material? What is its unit?
Last Answer : Dielectric Strength: The dielectric strength of an insulating material is the maximum voltage which the insulating medium can withstand without breakdown. Unit is volts per millimeter (V/mm), or kV/mm or kV/cm
Description : The insulating material should have (a) low permittivity (b) high resistivity (c) high dielectric strength (d) all of the above
Last Answer : (d) all of the above
Description : The insulating material for a cable should have (a) low cost (b) high dielectric strength (c) high mechanical strength (d) all of the above
Description : State failure phenomena observed in insulating material. State four reasons for failure of gaseous and solid dielectric materials.
Last Answer : Failure phenomena in insulating material means the dielectric property fails : The dielectric failure mean the dielectric strength of insulating material reduces due to high voltages or high ... 6. Due to poor maintenance of insulating material there may be possibility dielectric failure
Description : Dielectric (A) Is an electrical insulating material (B) Of low resistivity is preferred (C) Should have high thermal conductivity (D) Need not defy the corrosive action of chemicals
Last Answer : (A) Is an electrical insulating material
Description : Mica is a (A) Dielectric material. (B) Insulating material. (C) Magnetic material. (D) Both insulating and dielectric material.
Last Answer : (D) Both insulating and dielectric material.
Description : Define dielectric failure of electrical insulating material.
Last Answer : Definition of dielectric failure of electrical insulating material. In the insulating material if the applied voltage is increased gradually then for certain value insulation will break down, ... material vanishes its insulating properties and starts conducting, also known as dielectric failure.
Description : What is good dielectric break down value for insulating oil?
Last Answer : 60 kV.
Description : The breakdown of insulation of the cable can be avoided economically by the use of (a) inter-sheaths (b) insulating materials with different dielectric constants (c) both (a) and (b) (d) none of the above
Last Answer : (c) both (a) and (b)
Description : Materials, which provide a path to the magnetic flux, are classified as (A) insulating materials. (B) semi conducting materials. (C) magnetic materials. (D) dielectric materials.
Last Answer : (C) magnetic materials.
Description : Dielectric materials are (A) Insulating materials. (B) Semiconducting materials. (C) Magnetic materials. (D) Ferroelectric materials.
Last Answer : (A) Insulating materials.
Description : Gold and silver are (A) dielectric materials (B) low resistivity conducting materials. (C) magnetic materials. (D) insulating materials.
Last Answer : (B) low resistivity conducting materials.
Description : Dielectric strength of a material is (A) Its energy storage capacity (B) A magnetic property (C) Its capacity to resist the flow of current (D) Its capacity to withstand high voltage
Last Answer : (D) Its capacity to withstand high voltage
Description : Describe dielectric strength of material.
Last Answer : Dielectric strength of material: Dielectric strength is the ability of a dielectric material of specified thickness to withstand at high voltage without breaking down. It is a measure of the strength of ... strength can withstand at high voltage. It is expressed in the unit of kV/cm.
Description : Define breakdown voltage and dielectric strength of a capacitor.
Last Answer : Breakdown Voltage: The voltage at which the dielectric material breaks down (Starts conducting or is no longer remains as an insulator) for a specified thickness, is called its breakdown ... without breaking down (without losing its dielectric property) is called its dielectric strength.
Description : Define : (i) Dielectric strength (ii) Breakdown voltage
Last Answer : (i) Dielectric strength: The voltage which a dielectric material can withstand without breaking down (without losing its dielectric property) is called its dielectric strength. It is represented by kV/mm ... or is no longer an insulator) for a specified thickness, is its breakdown voltage.
Description : Define dielectric strength for a capacitor.
Last Answer : Ans: Di-electric Strength for a capacitor: The voltage which a dielectric material can withstand without breaking down (without losing its dielectric property) is called as dielectric strength.
Description : The dielectric strength of impregnated papers is about (a) 20 kV/mm (b) 30 kV/mm (c) 15 kV/mm (d) 5 kV/mm
Last Answer : The dielectric strength of impregnated papers is about 30 kV/mm
Description : If the loss tangent is very less, then the material will be a a) Conductor b) Lossless dielectric c) Lossy dielectric d) Insulator
Last Answer : b) Lossless dielectric
Description : State two applications of : (i) PVC paper (ii) Porcelain with type of class based on withstand temperature is insulating material.
Last Answer : (i) Application of PVC paper : 1. It is used in slot lining or motor winding insulation purpose 2. For Insulation of Transformer winding (ii) Application of Porcelain : 1. Mainly used for manufacturing ... on withstand temperature : * H' & C' Class of insulation i e. 180° and above 180°C
Description : State gaseous and liquid insulating material.
Last Answer : i) Gaseous insulating material : 1. Air 2. Nitrogen 3. Hydrogen 4. SF6 ii) liquid insulating material: 1. Transformer oil 2. Capacitor oil 3. Cable oil 4. Pyranol 5. Savotal 6. Savol 7. Vegetable oil 8. Silicon liquids
Description : Based on temperature withstanding ability, classify insulating material.
Last Answer : class Temperature withstanding ability in 0C Materials Y 90 Cotton, silk paper and similar organic materials neither impregnated nor immersed in any oil, rubber, PVC. A 105 ... rubber compounds C Above 180 Mica, ceramics, glass, Teflon, quartz, etc.
Description : List four examples of insulating material and explain any two.
Last Answer : Examples of insulating materials: i) Solid: Ceramic, Porcelain, Mica, Glass, Rubber, Resinous, Fibers ii) Liquid: Synthetic, Mineral etc. iii) Gaseous: Hydrogen, Air, ... and low hygroscopicity. Uses: Insulation in electric field, transformer stampings, armature, pole stampings
Description : What are insulating material?
Last Answer : Insulating material: Insulating material is that which offers very high resistance to the flow of current through it.
Description : State the temperature with standing capacity of following class-insulating material class Y, class A, class B, class E. Also state two examples for each.
Last Answer : S.No Class of Insulating material Temperature withstanding capacity 0C Examples 1 Class Y' 900C Cotton, Silk paper and similar organic materials neither impregnated nor ... E' 1200C Cotton fabric, synthetic resin enamels. Paper laminates and Powder plastics
Description : Give classification of insulating materials on the basis of state of material and give one application of each.
Last Answer : Classification of Insulating material State of material Application Solid insulating materials Wood, rubber, plastic, PVC, glass, porcelain, mica, Polypropylene film etc. ... Switchgears, gas pressures cables, circuit breakers, generator cooling systems and X-ray apparatus
Description : The electric breakdown strength of insulating materials depends on (A) Nature of applied voltage (B) lmperfection of dielectric material (C) Pressure, temperature and humidity (D) All or these
Last Answer : The electric breakdown strength of insulating materials depends on (A) Nature of applied voltage (B) lmperfection of dielectric material (C) Pressure, temperature and humidity (D) All or these
Description : With the help of which bridge are the capacitance and dielectric loss of a capacitor generally measured ?
Last Answer : With the help of Schering bridge are the capacitance and dielectric loss of a capacitor generally measured.
Description : The measurement of dielectric loss and power factor is done using (A) Weins Bridge (B) Hays Bridge (C) Schering Bridge (D) Wheat Stone Bridge
Last Answer : C Schering brigde
Description : Write one application for the give dielectric material. (i) Polyvinyl Carbide(PVC) (ii) Glass (iii) Mica (iv) Cotton and Silk
Last Answer : (i) Polyvinyl Carbide(PVC):it is used in insulation of wires and cables in domestic wiring as well as in aircraft and factory wiring (any one) (ii) Glass: 1) Alkaline glasses are used for ... with wax or varnishes are used in windings of magnet coils and small medium sized mechanics (any one)
Description : Why is the dielectric strength of vacuum infinite?
Last Answer : The dielectric strength of vacuum is infinite because there isno molecule in the vacuum.
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 : 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 : 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 : The dielectric strength of a vacuum or dry air is approximately ________________. A. 450 volts/inch B. 1000 volts/inch C. 20-kv/inch D. 50-kv/inch
Last Answer : Answer: C
Description : A megohmmeter is used to measure _____________. A. voltage B. dielectric strength C. current D. power
Description : When using a megohmmeter to test the dielectric strength of wire insulation, a continuous series of slight downscale kicks by the pointer is result of ____________. A. good insulation B. the ... dirty insulation C. the capacitance of the windings D. the dielectric-absorption effect of the insulation
Description : When a megohmmeter is used to test the dielectric strength of wire insulation, the initial dip of the pointer toward 'zero' is caused by _____________. A. good insulation B. the leakage of ... of dirty insulation C. the capacitance of the circuit D. the dielectric absorption effect of the insulation
Description : Which of the following statements about copper wire sized by the AWG rating is correct? A. Number 12 AWG wire has a higher current rating than number 10 AWG wire. B. Number 10 AWG wire has a higher ... Number 12 AWG wire at 25°C has more resistance per 1000 feet than No. 10 AWG wire at 25°C.
Description : Which of the following statements concerning copper wire sized by AWG numbers is correct? A. Number 12 AWG wire has a higher current rating than 10 AWG wire. B. Number 12 AWG wire at 25°C has more ... dielectric strength than 12 AWG wire. D. Number 12 AWG wire is larger than number 10 AWG wire.
Description : Which of the following tests is not done for transformer oil? (A) Flash point and acid value (B) Aniline point (C) Dielectric strength (D) Copper strip corrosion test
Last Answer : (B) Aniline poin
Description : What is meant by Dielectric strength?
Last Answer : The maximum electrical potential gradient that a material can withstand without rupture usually specified in volts/millimeter of thickness. This also has known as electric strength.
Description : If a cable of homogeneous insulation has a maximum stress of 10 kV/mm, then the dielectric strength of insulation should be (a) 5 kV/mm (b) 10 kV/mm (a) 15 kV/mm (d) 30 kV/mm
Last Answer : (b) 10 kV/mm
Description : Dielectric strength of rubber is around (a) 5 kV/mm (b) 15 kV/mm (c) 30 kV/mm (d) 200 kV/mm
Last Answer : (c) 30 kV/mm
Description : How is the dielectric strength of an insulator determined?
Last Answer : By raising the voltage on a test sample until it breaks down.
Description : Define dielectric strength.
Last Answer : The ability of the insulation material to withstand potential difference.
Description : 63 The dielectric strength of transformer oil is expected to be A. 1kV B. 33kV C. 100kV D. 330 kV
Last Answer : B. 33kv
Description : The dielectric strength of transformer oil should be (A) 100 V. (B) 5 KV. (C) 30 KV. (D) 132 KV.
Last Answer : (C) 30 KV.
Description : Define Dielectric Strength for transformer oil. State its value for new transformer oil.
Last Answer : Dielectric strength is defined as the maximum voltage that can be applied to across to the Fulid with out electrical breakdown is called Dielectric strength.
Last Answer : Dielectric Constant and Dielectric Strength are same.