Please Log in or Register for more.

What is the definition of extra low voltage?

134 views

1 Answer

Answer :

Extra-low voltage (ELV) is an electricity supply voltage in a range which carries a low risk of dangerous electrical shock.

Like 1 like

Please log in or register to answer this question.

Related Questions


What is the difference between a line voltage and low voltage control system?

Show More

117 views 0 answers







What is considered low voltage and high voltage?

Show More

76 views 0 answers







What is Extra High Voltage?

Show More

72 views 0 answers







Step-down transformer converts high voltage and low current into:  (A) How voltage and high current (B) High voltage and low current (C) Low voltage and high current (D) None of the above
Last Answer : Step-down transformer converts high voltage and low current into: Low voltage and high current

Show More

123 views 1 answer







Which of the following is the least expensive protection for over current in low voltage system?  (A) Rewireable fuse (B) Isolator (C) Oil Circuit breaker (D) Air break circuit breaker
Last Answer : Which of the following is the least expensive protection for over current in low voltage system?  (A) Rewireable fuse (B) Isolator (C) Oil Circuit breaker (D) Air break circuit breaker

Show More

260 views 1 answer







What is meant by extra high voltage transmission?
Last Answer : HT & LT  two types transmission in industrial line 

Show More

186 views 1 answer







Low voltage cables are meant for use up to (a)l.lkV (b)3.3kV (c)6.6kV (d)llkV

Show More

0 views 0 answers







Why does surge impedance loading (SIL) increase with increase in voltage level?
Last Answer : Answer: SIL varies as the square of the operating voltage, so SIL increases with increase in voltage level

Show More

24 views 1 answer







Electro-mechanical voltage regulators are generally used in (a) reactors (b) generators (c) transformers (d) all of the above
Last Answer : (b) generators

Show More

11 views 1 answer







When an alternator connected to the bus-bar is shut down the bus-bar voltage will (a) fall (b) rise (c) remain unchanged (d) none of the above
Last Answer : (c) remain unchanged

Show More

18 views 1 answer







The frequency of voltage generated, in case of generators, can be increased by (a) using reactors (b) increasing the load (c) adjusting the governor (d) reducing the terminal voltage (e) none of the above
Last Answer : (c) adjusting the governor

Show More

10 views 1 answer







When the interconnector between two stations has large reactance (a) the transfer of power will take place with voltage fluctuation and noise (b) the transfer of power will take place with least loss ... out of step be¬cause of large angular displacement between the stations (d) none of the above
Last Answer : (c) the stations will fall out of step be¬cause of large angular displacement between the stations

Show More

14 views 1 answer







For transmission of power over a distance of 500 km, the transmission voltage should be in the range (a) 150 to 220 kV (b) 100 to 120 kV (c) 60 to 100 kV (d) 20 to 50 kV
Last Answer : (a) 150 to 220 kV

Show More

40 views 1 answer







Constant voltage transmission entails the following disadvantage (a) large conductor area is required for same power transmission (b) short-circuit current of the system is increased (c) either of the above (d) none of the above
Last Answer : (b) short-circuit current of the system is increased

Show More

12 views 1 answer







In a tap changing transformer, the tappings are provided on (a) primary winding (b) secondary winding (c) high voltage winding (d) any of the above
Last Answer : (b) secondary winding

Show More

50 views 1 answer







Which of the following equipment, for regulating the voltage in distribution feeder, will be most economical ? (a) Static condenser (b) Synchronous condenser (c) Tap changing transformer (d) Booster transformer
Last Answer : (d) Booster transformer

Show More

19 views 1 answer







For transmission of power over a distance of 200 km, the transmission voltage should be (a) 132 kV (b) 66 kV (c) 33 kV (d) 11 kV
Last Answer : (a) 132 kV

Show More

53 views 1 answer







The voltage drop, for constant voltage transmission is compensated by installing (a) inductors (b) capacitors (c) synchronous motors (d) all of above (e) none of the above
Last Answer : (c) synchronous motors

Show More

11 views 1 answer







By which of the following a bus-bar is rated ? (a) Current only (b) Current and voltage (c) Current, voltage and frequency (d) Current, voltage, frequency and short time current
Last Answer : (d) Current, voltage, frequency and short time current

Show More

16 views 1 answer







Transmission voltage of ll kV is normally used for distances upto (a) 20—25 km (b) 40—50 km (c) 60—70 km (d) 80—100 km
Last Answer : (a) 20—25 km

Show More

15 views 1 answer







The power transmitted will be maximum when (a) corona losses are minimum (b) reactance is high (c) sending end voltage is more (d) receiving end voltage is more
Last Answer : (c) sending end voltage is more

Show More

30 views 1 answer







Which of the following is usually not the generating voltage ? (a) 6.6 kV (b) 8.8 kV (c) 11 kV (d) 13.2 kV
Last Answer : (b) 8.8 kV

Show More

33 views 1 answer







As compared to a 2-wire D.C. distributor, a 3-wire distributor with same maximum voltage to earth uses only (a) 31.25 percent of copper (b) 33.3 percent of copper (c) 66.7 percent of copper (d) 125 percent of copper
Last Answer : (a) 31.25 percent of copper

Show More

18 views 1 answer







Transmitted power remaining the same, if supply voltage of a D.C. 2-wire feeder is increased 100 percent, saving in copper is (a) 25 percent (b) 50 percent (c) 75 percent (d) 100 percent
Last Answer : (b) 50 percent

Show More

33 views 1 answer







In a D.C. 3-wire distribution system, balancer fields are cross-connected in order to (a) boost the generated voltage (b) balance loads on both sides of the neutral (c) make both machine^ run as unloaded motors (d) equalize voltages on the positive and negative outers

Show More

6 views 0 answers







The material generally used for armour of high voltage cables is (a) aluminium (b) steel (c) brass (d) copper
Last Answer : (b) steel

Show More

32 views 1 answer







The material commonly used for insulation in high voltage cables is (a) lead (b) paper (c) rubber (d) none of the above
Last Answer : (b) paper

Show More

16 views 1 answer







High voltage transmission lines use (a) suspension insulators (b) pin insulators (c) both (a) and (b) (d) none of the above
Last Answer : (a) suspension insulators

Show More

21 views 1 answer







Most of the high voltage transmission lines in India are (a) underground (b) overhead (c) either of the above (d) none of the above
Last Answer : (b) overhead

Show More

27 views 1 answer







The voltage of the single phase supply to residential consumers is (a) 110 V (b) 210 V (c) 230 V (d) 400 V
Last Answer : (c) 230 V

Show More

14 views 1 answer







Which of the following is the demerit of a 'constant voltage transmission system' ? (a) Increase of short-circuit current of the system (b) Availability of steady voltage at all loads at ... of carrying increased power for a given conductor size in case of long-distance heavy power transmission
Last Answer : (a) Increase of short-circuit current of the system

Show More

19 views 1 answer







The phenomenon qf rise in voltage at the receiving end of the open-circuited or lightly loaded line is called the (a) Seeback effect (b) Ferranti effect (c) Raman effect (d) none of the above
Last Answer : (b) Ferranti effect

Show More

25 views 1 answer







Which of the following characteristics should the line supports for transmission lines possess ? (a) Low cost (b) High mechanical strength (c) Longer life (d) All of the above
Last Answer : (d) All of the above

Show More

10 views 1 answer







Explain some of the methods to improve the strength of transmission system?
Last Answer :  Introducing or adding of new transmission lines in to the system to avoid the overloading of the existing lines  Application of devices such as series capacitors in the right location of ... system  Adoption of multi-voltage levels an multi-circuits in the existing ac transmission system

Show More

18 views 1 answer







What are the factors that limit the maximum power transfer capability in a transmission line?
Last Answer : Answer: Some of the factors which limits the maximum power transfer are: 1. Electrical phase shift 2. Voltage drop 3. Thermal effects in the line

Show More

39 views 1 answer







What are the problems associated with EHV transmission?
Last Answer : Answer: The problems associated with EHV transmission are corona loss and radio interference, requirement of heavy supporting structures and insulation requirments

Show More

12 views 1 answer







What is the material used for overhead transmission lines?
Last Answer : Answer: ACSR conductors are employed.

Show More

9 views 1 answer







What for series and shunt compensation provided in EHV transmission lines?
Last Answer : Answer: Series capacitance is provided in EHV lines to artificially reduce the series reactance of the line so as to improve stability, voltage regulation and transmission efficiency Shunt compensation ... reduce the line susceptance so as to improve the voltage regulation under light load condition

Show More

19 views 1 answer







Series capacitors on transmission lines are of little use when the load VAR requirement is (a) large (b) small (b) fluctuating (d) any of the above
Last Answer : (b) small

Show More

16 views 1 answer







The angular displacement between two interconnected stations is mainly due to (a) armature reactance of both alternators (b) reactance of the interconnector (c) synchronous reactance of both the alternators (d) all of the above
Last Answer : (a) armature reactance of both alternators

Show More

20 views 1 answer







In the analysis of which of the following lines shunt capacitance is neglected ? (a) Short transmission lines (b) Medium transmission lines (c) Long transmission lines (d) Medium as well as long transmission lines
Last Answer : (a) Short transmission lines

Show More

35 views 1 answer







The effect of corona can be detected by (a) presence of ozone detected by odour (b) hissing sound (c) faint luminous glow of bluish colour (d) all of the above
Last Answer : (d) all of the above

Show More

12 views 1 answer







For aluminium, as compared to copper, all the following factors have higher values except (a) specific volume (6) electrical conductivity (c) co-efficient of linear expansion (d) resistance per unit length for same cross-section
Last Answer : (6) electrical conductivity

Show More

11 views 1 answer







Aluminium has a specific gravity of (a) 1.5 (b) 2.7 (c) 4.2 (d) 7.8
Last Answer : (b) 2.7

Show More

4 views 1 answer







Pin type insulators are generally not used for voltages beyond (a) 1 kV (b) 11 kV (c) 22 kV (d) 33 kV
Last Answer : (d) 33 kV

Show More

16 views 1 answer







The current drawn by the line due to corona losses is (a) non-sinusoidal (b) sinusoidal (c) triangular (d) square
Last Answer : (a) non-sinusoidal

Show More

11 views 1 answer







The use of strain type insulators is made where the conductors are (a) dead ended (b) at intermediate anchor towers (c) any of the above (d) none of the above
Last Answer : (c) any of the above

Show More

10 views 1 answer







In a substation the following equipment is not installed (a) exciters (b) series capacitors (c) shunt reactors (d) voltatre transformers
Last Answer : (a) exciters

Show More

11 views 1 answer







For which of the following equipment current rating is not necessary ? (a) Circuit breakers (b) Isolators (c) Load break switch (d) Circuit breakers and load break switches

Show More

7 views 0 answers







A circuit is disconnected by isolators when (a) line is energized (b) there is no current in the line (c) line is on full load (d) circuit breaker is not open
Last Answer : (b) there is no current in the line

Show More

4 views 1 answer






Show More⇦ PreviousNext ⇨