Compassionate Ground Appointment

Compassionate ground appointment in Railway

What is a Compassionate Ground Appointment?

The compassionate ground appointment is a scheme that allows for the appointment of a dependent eligible family member of a deceased/ medically incapacitated/ de-categorized/ missing railway employee to a suitable post within the Indian Railways. This appointment is granted to the eligible family members to enable the family of the deceased/ incapacitated/ de-categorized/ missing to get over the sudden financial crisis.

Eligibility Criteria:

To be eligible for a compassionate ground appointment, the following conditions must be fulfilled:

  • The employee must have served or be undergoing pre-requisite training in the Indian Railways.
  • The death/ medical incapacitation/ de-categorization/ missing status of the employee should have    
     resulted in a financial crisis for the family.
  • The applicant for compassionate appointment should be the spouse, son, daughter, or dependent     
     family member of the deceased/medically incapacitated/ de-categorized/ missing employee.
  • The applicant must meet the prescribed educational qualification, medical standard and age requirements for the post, subject to any exemptions.

Circumstances of Compassionate Appointments:

Appointments will be made to the dependents of the Railway servants in the following cases, provided other conditions are met:

  • Loss of life or total invalidation/ incapacitation in the course of duties.
  • Death in service before retirement on superannuation.
  • Medical incapacitation/ invalidation of an employee (upon acceptance of voluntary retirement).
  • Medically de-categorized staff having at least 05 years or more service remaining on the date of being declared medically de-categorized (upon acceptance of voluntary retirement). With a condition for appointment in only level-1 posts.
  • When an employee’s whereabouts are not known or the employee is found Missing, subject to applicable conditions.

Eligible Family Members for Appointment in Railways (regular employee cases):

  • Spouse (wife or husband) of the employee.
  • Son, Daughter (unmarried, married, widowed, divorced) including adopted son or daughter as per rules.
  • If a widow/widower is unable to take up employment and wishes to nominate their minor son or daughter for the appointment, a “minor case” may be registered. The case will be kept pending until the child reaches the age of majority.
  • Dependent Brother or Sister in case of an unmarried employee as per rules.

Eligible Family Members for Appointment in Railways (trainee cases):

Compassionate Appointment case: If the ward of a deceased employee, who was appointed on compassionate grounds, passes away or becomes medically incapacitated during the pre-requisite training, the spouse of the deceased employee may be allowed to nominate another ward, themselves, or the widow/wife of the deceased/medically incapacitated trainee for compassionate appointment consideration. This provision ensures that the family continues to receive support in case of unfortunate circumstances affecting the appointed ward.

In case the spouse of the deceased employee is not alive for nomination then:

a) If the deceased/medically incapacitated CGA (Compassionate ground appointed) trainee is married then the widow/wife of the deceased/medically incapacitated CGA trainee may be considered for CGA.

b) If the deceased/medically incapacitated CGA trainee is unmarried then another ward of the original employee may be considered for CGA.

ii) RRB/RRC/Open recruitment-In situations where an employee appointed against regular and substantive posts through RRB/RRC/Open recruitment passes away before completing the mandatory training required for regularization, the spouse of the trainee employee will be eligible for consideration for a compassionate ground appointment.

Application Process:

To apply for a compassionate ground appointment, follow these steps:

  • The application form shall be handed over to the family members by the concerned Welfare Inspector.
  • Fill out the application form with accurately, if any doubt may kind consult the sectional Welfare Inspector.
  • Attach the necessary documents, as indicated in the checklist.
  • Submit your application along with the supporting documents to the concerned Sectional Staff and Welfare Inspector within the specified time period.
  • If required, you may also submit your application by post to the designated address

Prescribed Time for Submission of Application:

  • Within 5 years of the date of death/medical invalidation etc.
  • Minor son/daughter: within 2 years of attaining majority, where the case was earlier registered for appointment as minor.

Educational Qualification:

Educational qualification possessed by the ward/spouse of the ex-employee at the time of submission of application for an appointment may be considered. for qualification details may kind refer the table given below.

Name of the postEducation qualificationPass markPsycho testRemarks
Graduate level posts: like Station master, Goods Train Manager, Sr. Clerk, JAA, Ch. Comml.Cum Ticketing Supervisor etc+ 3 Arts, Science, Commerce in any discipline, Any Technical graduate40 marks out of 100 as per present policy.Only for Station master post.GM approval is required for appointment in ministerial post like Sr.Clerk and JAA.
Under Graduate level post: like Jr.TNC, Jr.Comml Cum Ticket Clerk, Jr.Clerk, Accounts Asst. Technician-III, ALP+ 2 Arts, Science, Commerce in any discipline, Any Technical graduate. For ALP post ITI, diploma is required40 marks out of 100 as per present policy.Only for ALP post.GM approval is required for appointment in ministerial post like Jr.Clerk and Accounts Asst.
JE (Mech./Civil/S&T/Elect. /Engg.), DMS (Depot Material Superintendent)Technical graduate in concerned discipline,60 marks out of 150 as per present policy.Not applicableDRM is empowered to consider such posts.  In Terms of RBE No. 181/2018.

Rules related to acquiring educational qualification. Related RBE No. 100/2019 & RBE No.21/2023.

a) If the candidate is a major at the time of death/medical invalidation of the ex-employee and is already admitted to a course, then he/she shall be allowed to complete the course (subject to a maximum limit of 5 years for completion of course) provided he/she takes due permission of Railway Administration and his/her case for appointment would be considered according to the qualification so acquired. Pursuing a course other than that to which the candidate had already been admitted at the time of death/invalidation of the late/ex. employee will not be allowed/counted for this purpose.

b) If the candidate is minor at the time of death/medical invalidation of the ex-employee but at the time of his/her attaining majority, he/she is already admitted to a course, he/she shall be allowed to complete the course (subject to a maximum limit of 5 years for completion of course) on taking due permission from Railway Administration and his/her case for appointment would be considered according to the qualification so acquired.

N.B. Widow/wife of late/ex-employee who does not possess the requisite minimum educational qualification may be considered against level-1 post subject to some on-job training. Related RBENo.51/2018.

Age Requirements and Relaxations:

i) 18 years of age should be completed for applying for an appointment in Railways on compassionate grounds. The lower age limit may be relaxed up to one year with the personal approval General Manager in merit of the case.

ii) If the candidate not completed 18 years of age he/she should be registered his/her case for employment assistance as a minor case.

iii) The Upper age limit may be freely relaxed at divisional level and DRM is empowered to relax upper age limit on the merits of the cases. Related RBE No. 145/2018.

Selection Procedure:

The selection procedure for compassionate ground appointments involves the following steps:

a) Verification of documents: like genuineness of educational certificate, caste certificate, legal heir certificate.

b) Assessment of financial condition: The financial condition of the family will be assessed to determine the level of crisis faced as advised in RBE No.03/2009.

c) Consideration by the competent authority: The application will be reviewed by a competent authority to assess the suitability of the applicant for appointment.

d) Passing the medical examination: The applicant must undergo a medical examination at the Divisional Railway Hospital and meet the prescribed medical standards. For appointment in ALP post one has to passed A-1 medical standard and  for SM (station master) & GTM (Goods Train Manager) post one has to passed A-2 medical standard. However if one candidate found lower than the above medical category he/she will be provided one post in railway definitely according to the medical standard. 

e) Suitability test and screening: If the applicant is aspiring for a post of Level-2 (7th CPC) or above, a suitability test based on educational qualifications will be conducted. Upon qualifying the suitability test, the candidate will undergo a screening process.

f) Issuance of appointment letter: If the above steps are satisfactorily completed, the offer of appointment shall be issued to the eligible candidate.

Time Limit for Consideration of Compassionate Ground Appointment:

Such cases not received within the prescribed period of 5 years from the date of death /medical invalidation or within 2 years of attaining majority will be considered as per the following schedule.

  1. Beyond 5 years and upto 20 years Divisional Railway Manager
  2. Beyond 20 years and upto 25 years General Manager
  3. Beyond 25 years Railway Board

Suitability Test:

The suitability of a candidate for an appointment on compassionate grounds is assessed through a monthly written test conducted specifically for this purpose. The written test serves as a means to evaluate the candidate’s suitability for the available post.

Note: For appointment in Level-1 posts in compassionate ground appointments, there is no suitability test or written test conducted only suitability of candidates is assessed by one APO as per present policy.

Number of Chances for Appearance of written test

The following number of chances to be given to the candidates for appearing suitability test for Group C posts (Level-2 and above) in Railways for appointment on compassionate ground . 

  • Wards/wife/widow- 2nd chance can be provided with approval of DRM at divisional level.
  • Widow/wife- 3rd & 4th chances will require the personal approval of the General Manager
  • Wards – 3rd chance will require the personal approval of the General Manager

N.B:- Wards are not provided 4th chance. If they remain unsuccessful in 3rd chance they will be considered for level-1 post automatically.

Grade of appointment:

Compassionate ground appointment is always made in recruitment grade that means against direct recruitment quota. Appointment can not be made in intermediate grade.

Transfer to other Railways/Division:

In case a request is received from the candidate for appointment on another Railway/Division his/her case may be transferred to that Railway/Division after the approval of the Competent Authority. Assessment of suitability may be done by the Railway/Division where the candidate is to be appointed. Only admissibility of the case is checked at the parent division/Railway. Related RBE No. 134/2018.

Priorities in Making Appointments:

The following should be the order of priority to be followed while making a Compassionate Grounds Appointment (CGA) in Railways:

Priority Occasion Time limit for CGA

  1. Dependents of employees who die or are permanently crippled in the course of duty 1 month
  2. Dependents of employees who die in harness as a result of railway or other accidents when off duty 3 months.
  3. Dependents of employees who are medically incapacitated/de-categorised and opt for voluntary retirement and other cases (3 months).

Appointment is NOT a Right:

(Hon’ble Supreme Court judgment in the case of Sri Umesh Kumar Nagpal Vs State of Haryana) [Estt. Sl.No. 72/95] The whole object of granting compassionate ground appointments is to give relief to the family of the bereaved person from a sudden crisis. Hence, the appointment of compassionate appointment should be considered after the assessment of the liabilities of the family.

20. Checklist of Documents to be attached with the application for Appointment:

  1. Employment assistance Application form
  2. Death certificate, Termination order of the ex.employee/VR order .
  3. Legal heir/Family member Certificate/Medical Identity card copies(UMID Card)/Pass Declaration Certificate
  4. Education Qualification Certificate(10th or Equivalent /Inter-mediate/Degree etc) copies-Provisional Certificate including mark sheet can be considered
  5. Date of Birth Declaration by illiterate Widow (vide Affidavit). In case of wards birth certificate.
  6. Discrepancy if any in the following and clarification through Declaration/Affidavit
  7. i) Name/DOB of the candidate, ii) Name of the Ex-Employee
  8. In the case of 2nd marriage, it should be certified as legally valid duly enclosing relevant documents.
  9. In the case of an adopted Son/Daughter, valid adoption deed and registration copies etc. Valid in the sense the adoption deed should be executed before death/invalidation of the ex.employee. further the same is to be verified from one law officer in regard to it’s validation.
  10. Voter ID, Ration card(if any)
  11. In delayed cases, the reasons for the delay are to be submitted by the applicant
  12. Movable/Immovable properties details, Spouse employment details to be furnished
  13. Aadhar card and PAN card of the applicant
  14. e-mail id and contact number to be provided

Model Question paper for Group C suitability test

Competent authority to make appointment on Compassionate Grounds.

 The powers for making compassionate ground appointment have been delegated to DRMs/CWMs.  But some certain cases approval of GM/Railway Board has been obtained.

General Manager permission is to be obtained in the following cases.

  • In case of appointment to the married / divorced / widowed daughter.
  • In case of appointment of wards of casual labour.
  • Relaxation of lower age limit up to one year.
  • Third chance to the widow/wards and 4th chance to the widow for appearing the written test on compassionate ground.
  • In case of appointment of gazetted officers.

In certain cases permission of Railway Board has also been required. These are as follows.

  • Relaxation of educational qualification.
  • Relaxation of lower age limit beyond one year.
  • Fixation higher pay and any other extra pay from the normal pay rule.
  • Time bared case more than 25 years.

Disclaimer:

Please note that the information provided above is general guidelines. The rules and regulations are revised from time to time by Railway  Board and  Zonal Head Quarters hence it is requested may kind refer the up to dated circulars and guidelines that has been issued from time to time. One can have no claim to the information provided in this website its meant only for information purpose.

Compassionate ground appointment in Railway

Picture credit goes to Google.com

Air Bags In Car

Air bags in Car

Air bags in car plays an important role during the time of car accident. Airbags are safety devices that are designed to inflate quickly during a collision or impact to cushion the occupants of a vehicle. They are typically installed in the steering wheel, dash, and/or doors of a vehicle. Airbags are most commonly found in cars, vans, and SUVs, but they can also be found in motorcycles and other wheeled vehicles. Most cars come with driver and passenger side airbags. Some cars may also have side airbags for the rear passengers, as well as curtain airbags for side-impact collisions. Some luxury vehicles may also have airbags for the driver’s and passenger’s knees.

Air bags in car being utilized at the time of accident.

Air bags used inside the car

The history of airbags in Car (four-wheelers) ?

Dates back to the 1970s when the first airbags were developed. The first airbags were developed by Ford Motor Company in the early 1970s and introduced in the Ford Pinto in 1974. These airbags were originally intended as a passive safety measure to protect occupants in the event of a crash. In the late 1980s, airbags became increasingly popular and began to appear in other models of cars. By the 1990s, most cars had at least one airbag, and many had more than one. Today, most cars have several airbags, including frontal, side, and curtain airbags, as well as knee airbags for the driver and front passenger. Airbags have become an important safety feature in cars, as they can help to reduce the severity of injuries in the event of a crash. They also help to keep occupants in their seats, which can help to prevent more serious injuries.

How air bag works in car?

An airbag in a four-wheeler works in much the same way as an airbag in a car. When an impact is detected, a sensor sends a signal to an electronic control unit (ECU). This ECU give signal to the inflation device, generally a small explosive, which immediately inflates the airbag in  fraction of a second. The force of the rapidly inflating airbag cushions the occupants of the vehicle and helps to reduce the impact of the crash.

What are the explosive used in air bag in four wheeler  ?

The most common explosive used in air bags for four wheelers is sodium azide. Other explosives used in air bags include potassium nitrate, ammonium nitrate, and tetrazole.

How air bags are works during the accident?

There are sensors in front of the automobile which detect the accident. The sensors send an electric signal to the electronic control unit (ECU)  that contains the sodium azide and the electric signal detonates a small amount of an igniter to the compound. The heat from this ignition starts the decomposition of the sodium azide and generate nitrogen gas (N2) to fill the air bag. It’s very interesting that from the time the sensor detects the collision to the time the air bag is fully inflated is only 30 milliseconds, the car’s occupant hits the air bag and its deflation absorbs the forward-moving energy of the occupant. Airbags are typically made of nylon fabric, and are filled with a mixture of nitrogen gas and sodium azide. When an airbag is deployed, the nitrogen gas and sodium azide are released, inflating the airbag in milliseconds. The airbag then quickly deflates, providing a cushion of air between the occupant and the interior of the vehicle.

Best air bags in four wheeler

  1. Bosch Airbag Systems
  2. Takata Airbag System
  3. TRW Airbag System
  4. Autoliv Airbag System
  5. ZF Airbag System
  6. Continental Airbag System
  7. Denso Airbag System

FAQs

Q-Can we install airbags in car in India?

A- Now a days many cars are manufactured with in build air bags but retrofitting of air bags is not possible as it is necessary to fit with it’s designed slot and also the arrangements of accident detect sensor is to be installed.

Q- Can I replace airbags in my car?

A- Once the air bags used during the accident it’s system is to be replaced with new one.

Q- Can airbags fail?

A- There may be possible of failing of air bag operation during the accident when technical error is occurred  in the sensor.

A-  For unbelted occupants and over the speed of 40 kmph.
Q-where are airbags located in a car?
A- Air bags are normally fitted in the dashboard of the car for safety of upper part of body of the          occupant.
Q- how do airbags protect you in terms of physics?
A-  At the time of accident the sensors send an electric signal to the electronic control unit (ECU)  that contains the sodium azide and the electric signal detonates a small amount of an igniter to the compound. The heat from this ignition starts the decomposition of the sodium azide and generate nitrogen gas (N2) to fill the air bag. Thus the air bag comes out from the dash board and inflate in front of the occupants and save the passengers from the dash board collision.
Pic credit to flickr and wikimedia

DC GENERATOR

DC GENERATOR

A generator is a machine which convert mechanical energy into electrical energy. In fact the mechanical energy is given to the armature for rotating in a magnetic field and an emf is produced in that armature. The following are the three requirements which is badly essential for a DC generator.

  1. Conductor
  2. Magnetic field
  3. Mechanical energy (for rotation of armature)

CONDUCTOR:- Insulated conductors are placed in armature slots.

MAGNETIC FIELD:- The magnetic field is obtained by using two ways like either permanent magnet or an electromagnet. Basically in all generator electromagnet is used and the reason behind is that, the electromagnetic field is easily controlled. These magnetic field is obtained in the pole shoe of the generator.

MECHANICAL ENERGY:- We need mechanical energy for rotation of the armature conductor and it can be obtained from the prime mover.  We can get it by using water turbine, steam turbine, diesel engine turbine.

WORKING PRINCIPLE OF DC GENERATOR

A generator works on the principle of “Faraday’s law of electromagnetic induction”. It states that, whenever a conductor is moved in the magnetic filed, an emf is generated in the conductors and the magnitude of the induced emf is directly proportional to the rate of cutting the flux.

                The emf generated in the conductor is actually alternating in nature but one commutator converts the alternating current into the direct current and the carbon brush collect the direct current and make it available in the external circuit. A dc generator can also be known as dynamo.

FLEMING’S RIGHT HAND RULE

 If the thumb, fore finger and middle finger of right hand stretched perpendicular to each other, then thumb will indicate the direction of motion of the conductor, fore finger will point the direction of magnetic lines of force and the middle finger will points the direction of induced emf. 

PARTS OF DC GENERATOR

YOKE-It is also known as body of the machine. The field poles are mounted in it. The main function of the yoke is to provide support to the armature and filed winding. It is also provide a close path for flowing of magnetic line of forces. It is made of cast iron or silicon steel.

FIELD POLE:- The pole shoes are screwed with yoke. They are made of cast steel or cast iron as it offers low reluctance to the magnetic line of forces.  All the field coils are connected in series (when it is four or six) in such a way as to produce opposite polarities at the adjacent poles. The functions of these poles are to support the field coils and to produce magnetic field in the machine.

The field poles are always electromagnet but in small machine permanent magnet is used. The narrow space between the pole shoe and armature is known as air gap.  

ARMATURE CORE & WINDING:- The armature is a cylindrical drum consisting of thin circular stampings of silicon steel  to (to reduce the hysteresis losses) and winding. The disks are insulated from each other by shellac varnish, thin paper or oxide film coating. The stamping sheets are mounted on a shaft. A commutator is fitted on one side and a cooling fan is fitted on another side. The core also provide low reluctance  for the flow of line of forces. Slots are also provide in it to keep the armature winding in it’s housing.

The armature performs mainly three functions such as

  1. It supports the conductor.
  2. It causes the conductor to rotate between the magnetic field.
  3. It provides low reluctance.

COMMUTATOR:-

It is electrical device which automatically reverses the direction of the coil. It consist of number of copper segments of high conductivity, hard drawn copper insulated from each other as well as from the shaft of the armature. One riser is also there attached with the commutator in which armature coil ends are soldered in it.

CLASSIFICATION OF DC GENERATOR

DC generators are of two types in accordance to magnetization of field.

  1. Permanent magnet generator :- In this generator field flux is produced by permanent magnet. Field flux of this generator remains constant, so the emf induced in such type of generator is always remains constant. 
  2. Electromagnet generator :- In this type of generator field flux is produced by passing the dc current through the field coils. The field coils are to be excited separately (from external dc source) or self induced emf.

Again Electro magnet generator divided into two types such as Self excited generator & separately excited generator. Again self excited generator are divided into three types like Series generator, shunt generator and compound generator. Compound generator is again divided into two types like long shunt compound generator and short shunt compound generator.

 Now there is question may arisen in your mind that, how separately excited generator works?

Ans- In this type of generator the field flux is produced by using external dc source like battery or another dynamo. Then after achieving the magnetic field, the armature rotate with the help of prime mover (it may be water turbine, diesel turbine etc.)

Then how self excited generator works?

Ans-In this generator some residual magnetism is also provided in the poles. When the armature rotates under the poles, due to the residual magnetism, some emf is induced in the armature winding (very small amount). Again this small amount of emf is applied across the field winding and the current flowing in such a way that it increases more emf in the armature conductors which further increases the flux and in this way the armature produces full rated voltage within a short time. Thus in self excited generator no external source is required to excite the field winding. As self induced emf is used to excite the field winding, it is known as self excited generator.  

Self excited generators are of three types such as ,

  1. Series Generator
  2. Shunt Generator
  3. Compound Generator

SERIES GENERATOR:-

DC SERIES GENERATOR

This generators are so named as the field winding is connected in series with the armature winding. The wire used in the armature and field winding is comparatively thick and few turns. This type of generator is run at full speed and the load switch is put on. Due to residual magnetism a small emf is produced when the external load is put on and the current flow between the load, armature and field winding. As the current in the field winding increases the armature produces more emf, thus the generator build up it’s emf.

In an open circuit or in no load the generator can not build up it’s voltage as there is no flow of current is possible.

SHUNT GENERATOR

DC SHUNT GENERATOR

In shunt generator the field winding is connected in parallel to the armature and thus the full voltage induced in the armature is applied to the shunt field. That is why the field winding is consisting of thin wire of many turns so as to drop the full voltage across it.  

When this generator is started a small amount of voltage is generated and this voltage is applied to the shunt filed which will build up more flux causes more emf to be induced in the armature and this goes on till the generator attains its full voltage. The load switch is kept open at that time of staring because the emf induced at that time is very small. If at the time of starting full load is connected in parallel to the field winding and armature, the current starts to flow in the load and not in the shunt field winding. This is because the resistance of the load is lower and current always flows through the easiest path. Thus there will not be enough current in shunt field winding and the generator will not build up voltage. This is why shunt generators are normally not started with full load.

COMPOUND GENERATOR

fo dc generator

This generators are with combination of armature, shunt field & series field winding. The shunt field is connected in parallel to the armature and designed with thin wire of many turns so as to carry full terminal voltage. The series field is designed with few turns thick wire so as to carry  full load current. The key point is that both the series field and shunt field winding are mounted on the same pole shoe and electrically separated from each other.

CLASSIFICATION OF COMPOUND GENERATOR

  1. Short shunt compound generator.
  2. Long shunt compound generator.

What is armature reaction? How it could be minimized ?

It is the effect of armature flux produced due to armature current  which then weakens the main magnetic flux produced  due to field winding. Due to this effect there is more sparking in the carbon brushes and low terminal voltage.

It can be minimized by adopting the following ways

  1. The carbon brushes must be shifted to new position of MNA (Magnetic Neutral Axis)
  2. Some extra turns are to be winded in field winding to neutralized the flux created due to armature current.
  3. Some slots are made in the pole shoe to drive the main flux toward to the centre of the pole. Actually the slot increased the reluctance at the TPT (Trailing pole tip)

What is Interpoles? How they are connected in the generator?

In large machine where the load is variable to minimize the cross magnetization interpoles are used and it is connected in series with the armature winding and are placed in the middle of the main pole. The polarity of the interpoles are same as that of main poles. It strengthens the main flux produced by the main pole and thus reduces the armature reaction.

COMMUTATION:-

Changing of current direction in the armature, when passing from the influence of one pole to the next is known as commutation. Actually when any two segments of the commutator come to the contact with a brush at a time, then a short circuit is caused between two armature coil. Due to commutation a heavy sparking is seen at the brush.  To minimize the commutation effect interpoles are also used.  

EMF EQUATION OF THE DC GENERATOR

When the armature is rotated, the emf induced in the conductor is directly proportional to the rate of change of cutting of magnetic lines of forces.

fo dc generatorEmf= ZN  X P

                60 X a

Where, P=Numbers of poles.

fo dc generator             = Flux per pole in web.

                N= Speed of armature in revolution/ Min

                Z= Total number of conductors on armature.

                a= Number parallel paths in armature.

                E= emf produced by one of the parallel paths in volts.

VOLTAGE REGULATION OF DC GENERATOR:- In order increase or decrease the terminal voltage we can use variable resistance or rheostat or voltage regulators. In shunt generator it is connected in series with the shunt field winding but in series generator it is connected in parallel to the series field winding.

APPLICATIONS OF DC GENERATORS:-

  1. Series Generators- it is used for arc lighting, arc welding and booster in electrical distribution.
  2. Shunt Generator:- As it gives constant voltage it is used for battery charging, electroplating, lighting,
  3. Compound Generator:- As this generator could maintain constant voltage at different load like cranes, trams and for traction load.

LOSSES IN GENERATOR:-

Generator transforms mechanical energy into electrical energy. That means by using mechanical energy it produces electrical energy. In this conversion the amount of input mechanical energy is not same amount electrical energy output.

Input mechanical energy = Output electrical energy + Looses

THE LOOSES IN DC GENERATOR

  1. Copper looses
  2. Iron looses
  3. Mechanical looses

FAQs

How does a dc generator work ?

When a conductor moves in magnetic field it cuts the magnetic lines of forces and an emf is induced in that conductor. The magnitude of induced emf is directly proportional to the rate of change of cutting the magnetic lines of forces. The emf is now available at the commutator and with the help of carbon brush we can collect the emf to the external circuit.

What are the used of DC generator ?

Generally dc generators are used for battery charging, lighting, electroplating etc.

What are the 3 types of DC generators?

There are mainly three types of DC generator according to field excitation, 1. Permanent magnet generator, 2. Self excited generator, 3. Separately excited generator.

Basic principle of dc generator ?

Generally DC generator works on the principle of Faraday’s law’s of electromagnetic induction. It states that, when a conductor linkage or cuts the magnetic lines of forces an emf is produced in it and the magnitude of induced emf depend upon the rate of cutting magnetic lines of forces.

DC MOTOR

fo dc generator

The machine which converts direct current (DC) electrical energy into mechanical energy is called direct current motor (DC Motor). The input energy which is given to the motor’s armature is Direct Current and the mechanical energy is available in the DC Motor shaft.

Working principle

When ever a current carrying conductor is placed in a magnetic filed it experiences some electromagnetic force and it tends to move. That means, here the current carrying conductor is the armature to which direct current is given through commutator and is placed in a magnetic field either it may be permanent magnetic field or electromagnetic filed, then an electromagnetic force will act on the current carrying conductor and it tends to move. The direction of force may be defined by Fleming’s left hand rule.

Construction of DC Motor

fo dc generator
Total internal parts of DC MOTOR

A dc motor is constructed with the following parts.

  • Outer body or Yoke or Frame
  • Field pole
  • Field winding
  • Field Shoe
  • Interpole
  • Armature or Rotor
  • Commutator
  • Brushes

Frame or Yoke or Outer body

It is the main part of a motor which made of generally cast iron and it’s shape is just like a cylinder and having two end cap also made of same metal to hold the armature. It holds the field pole and also make a magnetic ceiling for non leakage of magnetic lines of forces. As the cast iron is cheaper than other material normally cast iron is used for yoke.

Field Pole

It is that part of a dc motor which hold the field winding and made of thin sheets of laminated silicon steel. The number field pole is always in even number i.e 02 or 04 etc. The field coils are so connected in series in such a way that to produce opposite polarities at the adjacent poles. The function of these pole is to hold the the field coils and to produce magnetic field in the dc motor.

Field Winding

It is the vital parts of a dc motor that, it made with super enameled copper wire shaped as per the field pole and it produces the magnetic filed whenever it energized by dc external source.

Field Shoe

It is so designed to distribute magnetic lines of forces uniformly between the poles of dc motor.

Interpole

It is a supplementary pole which is placed between the main filed pole (90* electrically) and is connected in series with armature winding. It is used to neutralize the armature reaction. It’s polarity is same that of main filed pole to it’s precedes.

Armature or Rotor

Armature of a dc motor
Armature of a dc motor

It is the rotating part of a dc motor, through which electrical supply is given to the machine. It is made of thin sheets of laminated silicon steel with cylinder shaped. It rotates about it’s axis and contains the armature winding in it’s slots. The armature is winded with copper conductor to produce the magnetic field which later interact with the main field winding then causes rotations of the armature or rotor of dc motor. One side of the armature is connected with commutator and another side is connected with a fan for cooling purpose as you seen in the above picture.

Commutator

Commutator of a dc motor
Commutator of dc motor which has been displayed without armature.

It is cylindrical in shape and consist of number of copper segments of high conductivity, hard drawn copper segments insulated from each other by means of mica. It’s main work is to reverse the current direction in the coil.

Brushes

It is made of carbon and rest on commutator against the spring tension. Through the carbon brush direct current is supplied to the armature.

Types of DC motor

There are three types of DC motor like

  • Dc series motor
  • Dc shunt motor
  • Dc compound motor.

Dc Series motor

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DC SERIES MOTOR

In the dc series motor the field winding is connected in series with armature. The series winding is of thick wire of few turns designed to carry the full load current as equal to the armature current. In this motor the line current is equal to the submission of armature current and series field current.

Application of dc series motor:- These motors have high starting torque on heavy load for which it is used in electric cranes, electric trains, hoists etc.

DC Shunt motor

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DC SHUNT MOTOR

In dc shunt motor the field winding is connected in parallel to the armature and the full line voltage is applied to both armature and field winding. So the shunt field winding is of thin wire of many turns.

Application of dc shunt motor:- As the shunt field resistance is constant and applied voltage at the particular time is constant, the shunt field current is also constant and the field flux is also constant. So the speed of dc shunt motor will be constant. Due to constant speed characteristics this motor is used in leaths machine, saw mills, blowers, wood working machine etc.

DC compound motor

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DC COMPOUND MOTOR

Dc compound motors are combination of dc series motor and dc shunt motor. This motor have one series winding connected in series with the field winding and one shunt field winding connected in parallel to the armature winding. The series filed winding is of thick wire of few turns and the shunt field winding is of thin wire of more turns. But in practical you can see that, the series field winding is wounded in the same pole of shunt field winding. The major portion of flux is produced by the shunt field winding.

Further this compound motor again divided in two types like,

  • Differential compound motor
  • Commulative compound motor

Differential compound motor

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DIFFERENTIAL COMPOUND MOTOR

In this motor the field produced by the series filed winding is opposite to the field produced by the shunt field winding as shown in the above figure. The flow of current in both the field winding is opposite to each other. In the same pole if the series field winding produces the north pole then the shunt field winding produces the south pole. These motors are normally not used where heavy load is put on the motor.

Commulative compound motor

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DC COMMULATIVE COMPOUND MOTOR

In this motor the series filed winding produces the flux which helps the shunt field flux. That means if the shunt filed winding is produces the north pole then series field winding is also produces the north pole. All the compound motors are normally commulative connected. When the load on this motor is increased the flux produced by the series field winding is also increased thus it results decrease in speed. However the decreasing speed is nominal as the major portion of fulx is produced by the shunt field winding. This motor has constant speed characteristics on different load.

Application of Dc commulative compound motor:- These motors are normally used where heavy load is suddenly put on the motor or put off . like elevators, rolling mills, punches, shears, heavy planners, conveyors etc.

Frequently asked question (FAQ)

What is Fleming’s left hand rule?

This rule is used to determine the direction of force acting on a current carrying conductor placed in a magnetic field. If the thumb, fore finger and middle finger of the left hand are stretched perpendicular to each other then the fore finger points the direction of magnetic field, the middle finger points to the direction of current flow then the thumb will point of the direction motion of the conductor.

What is back e.m.f ?

When the armature of a motor rotated in the magnetic field, it cuts the magnetic line of force and an emf is induced in it. This induced e.m.f opposes the applied e.m.f and therefore it is called opposing e.m.f or back e.m.f or counter e.m.f.

What will happen if d.c. series motor is started without load ?

Due to low field flux the motor will run at a very high speed which may cause harm to the motor and injury to the operator. (The speed is inversely proportional to the field flux).

What are the common methods of speed control of d.c motors ?

There are two common method for speed control i.e 1-Field control method and 2- Armature control method . In field control method more than normal speed can be achieved but in field control method speed only can be reduced with respect to its normal speed. 

SAIL Recruitment 2022: Do you want to apply for ITI Jobs in Steel Authority of India Limited, Rourkela Steel Plant Right Now.

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SAIL Recruitment 2022, Rourkela steel plant (RSP) SAIL (Steel Authority of India Limited), A Maharatna Enterprises under Govt. Of India, has issued an official notification vide his Advt. No. 01/2022, Date: 29/08/2022 for recruitment of some executive and non executive posts. SAIL has invited application for fill up of these executive and non executive posts. Total number of vacancy notified is 333.

Job Opportunity through SAIL Recruitment 2022 (RSP, Odisha)

It’s a golden chance for the candidates having ITI qualification (i.e. ITI Jobs) to engage themselves in a Maharatna Enterprises Govt. of India, i.e SAIL (Steel Authority of India) in it’s RSP (Rourkela Steel Plant) branch based at Odisha. Attendant Cum Technician Trainee is the particular posts which coming under Non executive posts, meant for ITI candidates.

SAIL Recruitment 2022, SAIL logo
SAIL Recruitment 2022, Be a member of Rourkela Steel

SAIL Recruitment 2022 Important Date

  • Starting date for on line registration 06.09.2022
  • Closing date for on line registration 30.09.2022
Place of postingsRourkela Steel Plant, Odisha
Name of postsAttendant cum technician trainee
Total Number of posts31 (Fitter-09, Electrician-10, Machinist-12)
Selection Process1. Computer Based Test
2. Trade Test or Skill Test
Test Center Rourkela, Bhubaneswar, Cuttack, Vishakhapatnam
Ranchi, Kolkata, Raipur
Date of ExaminationWill be notified later
Venue of examination (City)As opted by the candidate during registration

SAIL Recruitment 2022 Age Limit:- 18 to 28 year as on 30/09/2022

Upper age relaxation:-

  • 05 years for SC/ST
  • 03 years for OBC (Non- Creamy layer)
  • 10 years for EWS/PWD

SAIL Recruitment 2022 Education Qualifications :-

Matriculation with ITI (full time) in the relevant trade of Fitter/Electrician/Machinist from Govt. recognized institute.

SAIL Recruitment 2022 Registration Fee:-

  • Rs.300 for UR/OBC
  • SC/ST/ESM and Departmental candidates- Nil registration fee.

SAIL Recruitment 2022 Exam Pattern :-

One CBT test comprising of 100 objective type question. Out of which 50 marks from technical knowledge and other 50 marks from Aptitude test. Then candidates who qualified in the CBT test needs to appear one viva test/ trade test and followed by a general medical test.

SAIL Recruitment 2022 Salary Structure:-

As per SAIL norms candidate appointed as Attendant Cum Technician Trainee will have to undergone two years training. In first year Rs. 12,900/month and in second year Rs. 15,000/month. Then candidates are regularised based on their good performance by placing them (S-1) grade start from Rs.25070-3%-35070/- plus other allowance as applicable.

SAIL Recruitment 2022 How to apply:-

Candidates are to follow the official website of SAIL,

https:// www.sailcareers.com or https://www.sail.co.in//

Download the notification in pdf. Click here.

Facilities Available:-

The life style of steel city is good as compared to other cities. More over after getting appointment in SAIL Recruitment 2022 one can avail well organized quarter with beautiful garden, and clean colony which will give you a peaceful life style to spent your service period at Steel City Rourkela. SAIL also provide well medical facilities in super specialist hospitals to you and your family members during your life threatening time. Thus job in SAIL may leads a perfect life style in every one life.

SAIL Recruitment 2022 Conclusion:-

From my experience i want to share some information that, this is an good opportunity for being a part of SAIL and in SAIL working atmosphere there is no feelings of superior and inferior that means everyone works in their position just like to complete the team work in the particular shift.