☞ Step up & down transformer visit
Do you know................................
(1) Difference between Nutral & Ground (earthing) ?
Ans : Nutral provide return path to current flow, earthing provide low resistive path to flow short circuit current during shock. Generally earthing provide human protection against shock during abnormal condition.
(2) What is voltage between Nutral and ground ?
Ans : 2 to 3 % of rated voltage
Ans : because first earthing pin come in contact to avoid shock experience which generally happen during plugin in shoket
(4) Difference between Line voltage & phase voltage ?
Ans : Line voltage always measure between two phase (live wire) and Phase voltage always measure between phase & Nutral wire.
☞ learn type of transformer visit
(5) How, 3-phase 400 V and single phase 230 V ?
Ans : In single phase we measured 230 V which is Phase voltage, But when we talk about 3-phase there 400 V is line voltage (not phase voltage)
👉So if calculate line voltage for 1-phase....
Line voltage (1-∅) = Vp/√3 = 230/√3 = 132.80 V
👉Now line voltage for three phase........
Line voltage (3-∅) = 3*133.80 = 400V
(6) Which Motor is use in ceiling fan ?
Ans : 1-phse Induction Motor (Capacitor start induction motor)
(7) difference between Star and delta
connections
Ans :
(8) Reactive Power is important or not ?
Ans : Yes
Reactive power is most important, without reactive power any induction machines not work like Motor, Transformer, etc.
(9) Why Reactive power is required?
Ans : Because due to reactive power flux is generate in core (mutual induction depend on reactive power) without reactive power induction is not happen.
☞ knowledge about DC Motor visit
(10) which is dengerous AC or DC ?
Ans : DC is most dengerous because it has a steady state characteristic during flow of current.
(11) what is power factor ?
Ans : it is nothing but the cosine angle between voltage and current.
(12) which value of power factor is good ?
Ans : Unity (Pf=1)
(13) how we can manage legging power factor ?
Ans : by connecting series capacitor.
(14) How we can manage leading PF
Ans : by connecting increasing the value of inductance.
(15) Main function of Capacitor ?
Ans : store a charge and provide when it's need it also use us filter in electronic circuits.
(16) Why we use AC transmission for long distance ?
Ans : In Ac power we can easily deals with transform to step up and step down voltage, because for long transmission we need high voltage to reduce transmission losses. which is difficult in DC system and also more dengerous.
(17) In LED bulb the more then one led dots is connected in...............
Ans : Series connection
(18) Generally what is ceiling fan rating in watt ?
Ans : 75 W to 100 W
(19) Which motor give hight starting torque ?
Ans : DC series Motor
(20) By which instrument we can measure intensity of light ?
Ans : Lux meter
(21) Hysteresis loss in electrical machines depend on..................
Ans : frequency
☞ induction motor visit
(22) Synchronous speed is given by ..........
Ans : Ns = 120f/P
Electrical full form visit
(23) MCB provide Protection Against ............
Ans : Over load Protection
(24) Fuse and other protective devices always connect in ..................wire.
Ans : Phase (Live) wire
☞ Which is Electrical Machine visit
(25) Why Resistor is coloured ?
Ans : by using resistor colour we can find value of resistance. each colour has a specific value .
☞ Induction motor
☞ Electrical Machine
☞ Transformer
☞ Step down and step up transformer
☞ DC Generator
☞ DC Motor
☞ What is insulation co-ordination ?
☞ Electrical Full forms
☞ Corona update ?
☞ English Sentence formation
☞ What is Facebook ?
☞ Electrical Machine
☞ Transformer
☞ Step down and step up transformer
☞ DC Generator
☞ DC Motor
☞ What is insulation co-ordination ?
☞ Electrical Full forms
☞ Corona update ?
☞ English Sentence formation
☞ What is Facebook ?
إرسال تعليق