Question bank for Energy Managers & Energy Auditors TERI, 4th Main, Domlur 2nd tage!angalore " #$% %&'Chapter 3.10: Energy Efficient Technologies in Electrical SystemsPart-I:Obecti!e type "#estions an$ ans%ers1. Maximum demand controller is used to ___________.a) switch off essential loads in a logical sequence b) exceed the demand of the plantc) switch off non-essential loads in a logical sequence d) controls the power factor of the plant2. Capacitors with automatic power factor controller when installed in a plant:a) reduces actie power drawn from grid b) reduces the reactie power drawn from gridc) reduces the oltage of the plant d) increases the load current of the plant!. _________ controls the power factor of the installation b" giing signals to switch on or off powerfactor correction capacitors.a) #$%&'() b) (utomatic power factor control rela"c) $ntelligent power factor controller d) Maximumdemand controller*. __________ determines the rating of capacitance connected in each step during the first hour of itsoperation and stores them in memor".a) Maximumdemand controller b) $ntelligent power factor controllerc) (utomatic power factor controller d) #$%&'()+. ,he following function can not be achieed with automatic power factor controllers. a) 'oltage controlb) #$%&'() control c) -. control d) /0 control1. ,he following features appl" to energ" efficient motors b" design:a) 2nerg" efficient motors last longer b) 3tarting torque for efficient motors ma" be lower than for standard motors3tate whether the two statements are ,rue or 0alse45. 2dd" current drie can be a retrofit for ________.a) constant speed s"stem requirement b) ariable speed s"stem requirementc) dual speed s"stem requirement onl" d) none of the aboe6. 2lectronic ariable frequenc" drie 7'08) connected to motors:a) proide ariable speed with high efficienc"b) induces edd"-current in the secondar" member of the clutch mechanismc) is not suitable for ariable torque loadd) does not proide ariable speed and has low-efficienc" 9. 'ariable speed can not be obtained with ____.a) 8C motors controller b) (C motor controllerc) soft starter controller d) (C : 8C controllers/var/www/apps/conversion/tmp/scratch_1/278869294.doc 73Question bank for Energy Managers & Energy Auditors TERI, 4th Main, Domlur 2nd tage!angalore " #$% %&'1;. 2nerg" saings potential of ariable torque applications compared to constant torque application is:a) higher b) lower c) equal d) none of the aboe11. (s an energ" efficient application< slip power recoer" s"stem fits well for ____.a) 3quirrel cage and slip ring motors b) 8C motorc) 3lip ring motors onl" d) =one of the aboe12. 2nerg" efficient transformer core is made up of ______.a) silicon allo"ed iron 7grain oriented) b) copperc) amorphous core - metallic glass allo" d) none of the aboe1!. ,he basic functions of electronic ballast excludes one of the following:a) to ignite the lamp b) to stabili>e the gas dischargec) to reduce lumen output of the lampd) to suppl" power to the lamp1*. 3elect the application of fluid coupling fitting from the following: a) acts as a oltage limiter b) enables no-load start-up of prime-moerc) wor-s on the principle of edd" current d) none of the aboe1+. ,he characteristic of conentional ballast in lighting application is one among the following:a) ,he" hae low operational losses than electronic ballasts.b) ,he" hae tuned circuit to delier power at 2+ ?>c) ,he" do not require a mechanical switch 7starter)d) ,he" hae high operational losses and high temperature rise11. (pplication of occupanc" sensors is well suited for ___.a) da" light based controllers b) night based controllersc) motor controllers d) moement or noise detector in room space15. 0ind the odd retrofit group from the following:a) &ccupanc" sensors b) timer based controlc) photo sensors d) capacitor based control16. (pplication of timers as a retrofit will assist in saing energ" in areas of ____. a) %ighting : motors b) ,ransformers c) ?'- 0eeder /anels d) (ll the aboe19. 2lectronic soft starters are used for motors to:a) achiee ariable speed b) proide smooth start and stopc) improe the loading c) none of the aboe2;. 2nerg" efficient lighting can be planned b" using the following retrofits. @ 3tate ,rueor 0alse a) photo-sensor b) timer c) occupanc" sensord) locali>ed switching /var/www/apps/conversion/tmp/scratch_1/278869294.doc 74Question bank for Energy Managers & Energy Auditors TERI, 4th Main, Domlur 2nd tage!angalore " #$% %&'Part-II:Short type "#estions an$ ans%ers1. ?ow maximum demand control can be practiced in a plant4 M8 control is er" important because the utilit" charges user not onl" for the energ" consumed butalso for the maximum demand made irrespectie energ" consumed 7as per two part tariff). ?ence inorder to reduce the energ" cost it is essential to control the maximum demand.M8 can be controlled b" Ase of maximum demand controller< 3taggering load during pea- load period b" sequencing of loads< operating in shifts etc. Maintaining er" good pf at pea- loads2. Briefl" explain the benefits of emplo"ing a demand controller (oids excess maximum demand on the suppl" grid ?elps in improing the load factor b" truncating the pea-s and flattening the load cure. (ssists in meeting expansion plans %eeling plant loads to aoid pea- load on feeder and electrical equipment!. .hat is (/0C4 .hat are its adantages4 (/0C is an acron"m for Cautomatic power factor controllerD. $t is used to improe the s"stem powerfactor b" automatic sensing of /0 correction and control.,he adantages of (/0C are Anmanned operation of pf control< (lwa"s maintains er" good and accurate pf 7as set)< )esults in decreased s"stemcurrent and hence reduced oltage drop and power lossautomaticall"< )educed energ" bill and aoids penalties both pf penalt" and maximum demand.*. =ame watt loss areas for improement b" using energ" efficient motors4 $ron loss 3tator $2) loss )otor $2) loss 0riction : windage 3tra" load loss+. .hat are the technical aspects of energ" efficient motors4 2nerg"-efficient motors last longer< andma" require less maintenance. (t lower temperatures