5.1 ELECTRICAL MACHINES - II L T P 4 - 3 RATIONALE .

1275.1ELECTRICAL MACHINES - IIL T P4 - 3RATIONALEElectrical machines is a subject where a student will deal with various types of electricalmachines which are employed in industries, power stations, domestic and commercialappliances etc. After studying this subject, an electrical diploma holder must becompetent to repair and maintain these machines and give suggestions to improve theirperformance. Explanation of practical aspects of the subject will make the studentscapable of performing various tests on the machines as per latest BIS specificationsLEARNING OUTCOMEAfter undergoing the subject, students will be able to:Demonstrate the constructional features of a synchronous machine and its workingas a synchronous motorOperate the synchronous motor as synchronous condenserUse 3- induction motor in the industry for various operationsOperate and maintain three phase squirrel cage and three phase slip usinginduction motors.Start and reverse the direction of rotation of three phase induction motors usingdifferent types of starters.Conduct speed control of three phase induction motor.Operate and maintain double cage induction motors.Recognize the condition of cogging and crawling in three phase induction motors.Operate different types of single phase induction motors.DETAILED CONTENTS1.Induction Motors1.11.21.31.41.51.61.71.81.91.10(36 hrs)Salient constructional features of squirrel cage and slip ring 3-phaseinduction motorsPrinciple of operation, slip and its significanceLocking of rotor and stator fieldsRotor resistance, inductance, emf and currentRelationship between copper loss and the motor slipPower flow diagram of an induction motorFactors determining the torqueTorque-slip curve, stable and unstable zonesEffect of rotor resistance upon the torque slip relationshipDouble cage rotor motor and its applications

1281.111.121.131.141.152.Starting of 3-phase induction motors, DOL, star-delta, auto transformerCauses of low power factor of induction motorsTesting of 3-phase motor on no load and blocked rotor test and to findefficiencySpeed control of induction motorHarmonics and its effects, cogging and crawling in Induction Motors.Single Phase Induction Motors2.1Singlephaseinduction(28 ons2.2Nature of field produced in single phase induction motor2.3Split phase induction motor2.3.12.3.22.3.3Capacitors start and run motorShaded pole motorReluctance start motor2.4Alternating current series motor and universal motors2.5Single phase synchronous motor2.5.12.5.2Reluctance motorHysteresis motorLIST OF PRACTICALS1.2.3.4.5.6.Study of ISI/BIS code for 3-phase induction motorsPerform at least two tests on a 3- phase induction motor as per BIS codeDetermination of efficiency by (a) no load test and blocked rotor test on aninduction motor (b) direct loading of an induction motor (refer BIS code)Determination of effect of rotor resistance on torque speed curve of an inductionmotorObserve the performance of a ceiling fan (I- ) induction motor) without capacitorTo observe effect of change in capacitor on the performance of 1-phase inductionmotorINSTRUCTIONAL STRATEGYTeacher should lay-emphasis on development of understanding amongst students aboutbasic principles of operation and control of electrical machines. This may be achieved byconducting quiz tests and by giving home assignments. The teachers should also conductlaboratories classes themselves encouraging each should to perform with his/her ownhands and draw conclusions.

129RECOMMENDED BOOKS1.Electrical Machines by SK Bhattacharya, Tata Mc Graw Hill, New Delhi2.Electrical Machines by SK Sahdev, Uneek Publications, Jalandhar3.Electrical Machines by Nagrath and Kothari, Tata Mc Graw Hill, New DelhiElectrical Engineering by JB Gupta, SK Kataria and sons, New Delhi4.Electrical Machines by Samarjit Ghosh, Pearson Education (Singapore) Pte, Ltd.482, FIE Patparganj, Delhi 1100925.Electrical Machines by DR Arora, Ishan Publications, Ambala City.SUGGESTED DISTRIBUTION OF MARKSTopic No12TotalTime Allotted(hrs)362864MarksAllocation (%)6040100

1305.2ELECTRICAL POWER – 1L T P4 - -RATIONALEThe majority of the polytechnic passouts who get employment in State Electricity Boardshave to perform various activities in the field of Generation, Transmission andDistribution of Electrical power. The range of these activities vary from simple operationand maintenance of equipment, lines, fault location, planning and designing of simpledistribution schemes, executive and supervisory control in power stations, transmissionand distribution networks in addition to administrative jobs including public relations.They should also be made aware of recent developments, current practices in theelectricity departments, corporations and boards to keep them abreast with moderntechniques in Transmission and Distribution of Electrical Power.LEARNING OUTCOMEAfter undergoing the subject, students will be able to:Distinguish and select suitable resource of energy required for a particular areaand environmentCalculate effective cost generationSelect suitable supporting structure, insulators, conductors and other accessoriesfor transmission lines and distribution linesPrepare layout plan for HT and LT lines/distribution systemPrepare estimate for HT and LT (OH and underground cables) linesOperate and maintain indoor and outdoor substationsUse various methods for improvement of power factorDETAILED CONTENTS1.Power Generation1.11.21.3(10 hrs)Main resources of energy, conventional and non-conventionalDifferent types of power stations, thermal, hydro, gas, diesel and nuclearpower stations. Flow diagrams and brief details of their operation,comparison of the generating stations on the basis of running cost, site,starting, maintenance etc.Importance of non-conventional sources of energy in the present scenario.Brief details of solar energy, bio-energy, wind energy

1312.Economics of Generation2.12.23.4.(08 hrs)Fixed and running cost, load estimation, load curves, demand factor, loadfactor, diversity factor, power factor and their effect on cost of generation,simple problems there on.Base load and peak load power stations, inter-connection of power stationsand its advantages, concept of regional and national grid.Transmission Systems(20 hrs)3.1Layout of transmission system, selection of voltage for H.T and L.T lines,advantages of high voltage for Transmission both AC and DC3.2Comparison of different system: AC versus DC for power transmission,conductor material and sizes from standard tables3.3Constructional features of transmission lines: Types of supports, types ofinsulators, Types of conductors, Selection of insulators, conductors, earthwire and their accessories, Transposition of conductors and stringefficiency of suspension type insulators, Bundle Conductors.3.4Mechanical features of line: Importance of sag, calculation of sag, effectsof wind and ice related problems; Indian electricity rules pertaining toclearance3.5Electrical features of line: Calculation of resistance, inductance andcapacitance without derivation in a.c. transmission line, voltage regulation,and concept of corona. Effects of corona and remedial measures3.6Transmission LossesDistribution System(14 hrs)4.1Lay out of HT and LT distribution system, constructional feature ofdistribution lines and their erection. LT feeders and service mains; Simpleproblems on AC radial distribution system, determination of size ofconductor4.2Preparation of estimates of HT and LT lines (OH and Cables).4.3Constructional features of LT (400 V), HT (II kV) underground cables,advantages and disadvantages of underground system with respect tooverhead system.4.4Calculation of losses in distribution system

1324.55.6.Faults in underground cables-determine fault location by Murray LoopTest, Varley Loop TestSubstations:(08 hrs)5.1Brief idea about substations; out door grid sub-station 220/132 KV, 66/33KV outdoor substations, pole mounted substations and indoor substation5.2Layout of 33/11 kV/400V distribution substation and various auxiliariesand equipment associated with iPower Factor:6.16.26.3(4 hrs)Concept of power factorReasons and disadvantages of low power factorMethods for improvement of power factor using capacitor banks, VAR Static Compensator (SVC)Note: students should visit power generation plants, sub-stations etc.INSTRUCTIONAL STRATEGYSince this is a descriptive and practice oriented subject, it is suggested that visits todifferent types of power generating stations and substations including grid stations bearranged and various equipment, accessories and components explained to the studentsbefore the actual class room teaching and make them familiar with the equipment andaccessories installed over there. There should be at least 3 visits during the semester. Thestudents may be asked to prepare notes while on visit and submit the report and giveseminar. In addition, viva-voce be conducted to evaluate the knowledge gained during thefield visit.RECOMMENDED BOOKS1.2.3.4.5.6.7.8.Electrical Power System and Analysis by CL Wadhwa, 3rd edition, New AgeInternational Publishers, New DelhiSubstation Design and Equipment by Satnam and PV Gupta, Dhanpat Rai & Sons,New DelhiElectrical Power –I by SK Sahdev, Uneek Publications, JalandharElectrical Power System by VK Mehta, S Chand and Co., New DelhiElectrical Power System by JB Gupta, SK Kataria and Sons, New DelhiSub-Station Design by Satnam, Dhanpat Rai and Co., New DelhiElectrical Power Distribution System by AS Pabla, Tata McGraw Hill, New DelhiElectrical Power System by S Channi Singh, Tata McGraw Publishing Co. NewDelhi

133SUGGESTED DISTRIBUTION OF MARKSTopic No.1Time Allotted(Hrs)10Marks Allocation(%)152081032035414205081060410Total64100

1345.3 PROGRAMMABLE LOGIC CONTROLLERS & MICRO CONTROLLERSL T P4 - 4RATIONALEA diploma holder when employed in automated industrial process controls or inautomated power station will be required to know the basics of Programmable LogicControllers, their working and their programming. In industry, many manufacturingprocesses demand a sequence of operation, which are to be performed repetitively. Earlyautomation systems were mechanical in design, timing and sequencing being effected bygears and cams. Slowly these design concepts were replaced by electrical drives whichwere controlled by relays and now by programmable logic controllers (PLCs). A PLC is asolid state device, designed to operate in noisy industrial environments and can performall logic functions. PLCs are widely used in all industries for efficient control operations.A diploma holder in industry is called upon to design , modify and troubleshoot suchcontrol circuits. Looking at the industrial applications of PLCs in the modern industry,this subject finds its usefulness in the present curriculum.Microcontrollers have also assumed great significance in the field of electronics andcomma goods industry, and thus considered to be an important field of engineering. Thissubject aims to expose the students to both of these and give them adequate knowledge ofthese topics.LEARNING OUTCOMEAfter undergoing the subject, students will be able to:Programme (ladder logic) to PLC for industrial processesChange conventional process to automationCheck and repair faults in domestic appliancesCheck and take corrective actions for programming in PLC’sInterface and sequence industrial processesNodify complicated processes with the help of PLCDETAILED CONTENTS1.Introduction to MicroprocessorsArchitecture of 8086, Pin Configuration(02 hrs)