What type of motor starting adopted in MCC?

1 Answer

Answer :

DOL (direct on line) starter.  

Related questions

Description : What is the safety reason to keep the contactor / MCC remote from motor?  

Last Answer : Contactor = sparking equipment. Not suiting for hazardous location.  

Description : What are the in-built protections provided in MCC cell? 

Last Answer : Fuses for short circuit protection. OLR for over load and single phasing protection. Electrical and Mechanical interlock in valve cell against short circuit. 

Description : Why 110V has been chosen in MCC cell? 

Last Answer : To isolate control circuit from power circuit for Human safety at control circuit side.  

Description : What is the safety interlock provided in MCC cell? 

Last Answer : The MCC cell door can't open if the cell is in on condition.  

Description : What is interlocks provided for the valve MCC 

Last Answer : a) Mechanical interlock, which will not allow the other contactor to close if one contactor, is closed. b) 42 auxiliary contacts are wired in the control ckt. 42-1 contact in 42-2 and 42-2 contact in 42-1. 

Description : What is the maximum load on MCC?

Last Answer : 3 Phase load upto 90 kW are fed by MCC. 

Description : Write details MCC construction. 

Last Answer : a) MCC are made up of sheet steel enclosure, indoor floor mounting and free standing, Dust and vermin proof, modular type and of double front and single front (X1, Y1). b) Degree of protection is IP 50 ... SRPH MCC are safety related and SB, TB, RAB, CWPH, DM Plant MCC's are non safety related. 

Description : What maintenance checks you will do for an MCC cells and MCC panel?

Last Answer : Maintenance checks on MCC cells a. Ensure that the load is tripped from control room and switch is in off position. Switch off the isolator at MCC cell. b. Open the door and rack ... See for proper earthing connection and tightness of the earthing connections. l. See for proper house keeping. 

Description : What are the advantages of MCC? 

Last Answer : a. Starters and contactors all will be a standard size. b. Spares inventory will be less. c. Cost of cables will be less because same size of cable is used for all capacity and gland holes can be provided before hand. d. Maintenance and trouble shooting is easier in MCC. 

Description : What are the logic’s adopted in barring gear motor?

Last Answer : For start permission a) Local or remote start. b) JOP is running. c) Motor hand barring is permissive. d) 42 contactor in MCC is off. e) Turbine speed is <100 rpm. Start permission (42S ... is >0.35 kg/ cm2. e) No thermal over load of 42. f) No one-DG condition. 

Description : In a faceplate-type motor starter, the starting arm is held in the 'OFF' position by a/an _____________. A. cotter pin B. magnet C. electrical circuit D. strong spring

Last Answer : Answer: D

Description : The rotor slots of a repulsion-type motor are generally skewed (placed nonparallel to the rotor axis) to _________. A. produce a constant starting torque B. permit a greater air gap with the starter C. permit a smaller air gap with the starter D. reduce eddy current losses

Last Answer : Answer: A

Description : In a 15 HP induction-type motor with a cage rotor, the current required at standstill to produce starting torque is approximately ____________. A. half the full load current B. equal to the full load current C. five times the full load current D. ten to twenty times the full load current

Last Answer : Answer: C

Description : What is the full form of 'MCC' ? -How To ?

Last Answer : The full form of 'MCC' is Maoist Communist Centre

Description : What is the full form of MCC ?

Last Answer : The full version of MCC is Marylebone Cricket Club (London).

Last Answer : MCC - Melbourne Cricket Club

Description : MCC is investigating the improvement of the relationship between people and computers through a technology called ___________ a) computer-aided design b) human factors c) parallel processing d) all of the mentioned

Last Answer : b) human factors

Description : The new organization established to implement the Fifth Generation Project is called _____________ a) ICOT (Institute for New Generation Computer Technology) b) MITI (Ministry of International ... c) MCC (Microelectronics and Computer Technology Corporation) d) SCP (Strategic Computing Program)

Last Answer : a) ICOT (Institute for New Generation Computer Technology)

Description : MCC includes ______ types of cloud resources A. 2 B. 3 C. 4 D. 5

Last Answer : 4

Description : Squirrel cage induction motor has a) Zero starting torque b) Very small starting torque c) Medium starting torque d) Very high starting torque

Last Answer : Ans: B

Description : The wiring diagram for the motor starting circuit shown in the illustration indicates ______________. EL-0007 A. resistance starting B. reduced voltage starting C. low voltage protection D. low voltage release

Last Answer : Answer: C

Description : A series wound DC motor has its armature and field connected in series with a resistor. When the motor is disconnected from its power supply, this motor will exemplify __________. A. the ... the proper connections for an automatic strip heater C. a reversing controller circuit D. dynamic braking

Last Answer : Answer: D

Description : Which statement is true concerning a split-phase induction motor? A. Motor rotation can be reversed without changing the windings or leads. B. Motor speed can be readily adjusted from zero to full ... proper wiring. D. Motor rotation can be reversed by reversing the leads on the starting winding.

Last Answer : Answer: D

Description : What is the main function in the use of a capacitor for starting a single phase motor? A. Reduce radio interference B. Split the phase to establish a rotating magnetic field C. Reduce the phase angle D. Prolong the life of the starting contacts

Last Answer : Answer: B

Description : A single-phase induction motor starts, comes up to about 75% rated speed, slows down to a lower speed, and accelerates again. The problem is most likely in the ____________. A. starting winding B. running winding C. starting capacitor D. running centrifugal switch

Last Answer : Answer: B

Description : A single-phase induction motor will only start if you spin the rotor rapidly with the line switch closed. After starting, its speed fluctuates between very slow and half-speed. The problem ... in the ________. A. starting winding B. centrifugal mechanism C. centrifugal switch D. running winding

Last Answer : Answer: D

Description : The advantage(s) of the method of D.C. motor speed control shown in the illustration is/are ______________. EL-0101 A. elimination of armature starting resistor losses B. elimination of speed instability with variable loads C. the ease of reversing motor direction D. all of the above

Last Answer : Answer: D

Description : If the centrifugal switch or relay used for cutting out the starting winding of a split-phase induction motor fails to open once the motor is in operation, the _____________. A. motor will overspeed B ... C. motor will immediately stall under load D. motor torque will be above normal at rated speed

Last Answer : Answer: B

Description : A single-phase induction motor fails to start. The rotor is spun rapidly with the line switch closed. Having started by this method it is noted that the motor fluctuates between a very slow ... lies in the ______ A. starting winding B. centrifugal mechanism C. centrifugal switch D. running winding

Last Answer : Answer: D

Description : Which of the following problems will most likely occur if the starting winding of a split-phase induction motor failed to cutout once the motor was in continuous operation? A. The motor will overspeed. B. The ... reduced speed. C. A time delay will stop the motor. D. The winding will burn out.

Last Answer : Answer: D

Description : Due to the operating characteristics of the system, time lag fuses (or dual-element fuses) are necessary for use in _____________. A. main lighting circuits B. motor starting circuit C. emergency lighting circuits D. general alarm circuits

Last Answer : Answer: B

Description : Motor starter or controller contacts may become welded together if the contacts _____________. A. open too quickly and arc B. close under excessive pressure C. open or close too quickly D. close under excessive starting current

Last Answer : Answer: D

Description : A characteristic of a wound-rotor induction motor, with a high resistance rotor winding, is _____________. A. low starting torque B. high starting torque C. high speed D. low starting voltage

Last Answer : Answer: B

Description : If an induction motor were to be operated at 90% rated voltage, _____________. A. there would be an increase in starting torque B. starting current would increase slightly C. synchronous speed would decrease slightly D. the slip would increase

Last Answer : Answer: D

Description : A characteristic of an induction motor with a low resistance rotor winding is _____________. A. high starting voltage B. high starting current C. high slippage D. low starting voltage

Last Answer : Answer: B

Description : Excessive heat in an operating motor controller can result from _____________. A. a closed starter contact B. loose connections C. missing arc chutes D. low motor starting torque

Last Answer : Answer: B

Description : When starting a DC propulsion motor the variable rheostat must FIRST be turned ____________. A. all the way to the run position then quickly back to slow B. to the slow position then gradually moved to full speed C. to the mid position D. quickly to the run position

Last Answer : Answer: B

Description : Reduced voltage applied to a motor during the starting period will _____________. A. result in decreased acceleration time only B. lower the starting current and increase accelerating time C. cause a greater starting torque D. increase the starting current and pump capacity

Last Answer : Answer: B

Description : Shading coils are installed on AC full-voltage starters to _____________. A. eliminate contact chatter B. dissipate opening contact arcs C. delay current build up in the holding coil D. protect the motor windings from momentary starting current overload

Last Answer : Answer: A

Description : A double squirrel-cage motor is designed to have __________. A. low starting torque B. low starting current C. high starting voltage D. low starting resistance

Last Answer : Answer: B

Description : A single-phase induction motor having a relatively high starting torque, is the ___________. A. shaded pole motor B. wound-rotor motor C. capacitor-start motor D. resistance-start motor

Last Answer : Answer: C

Description : The purpose of squirrel-cage windings in a synchronous motor is to ______________. A. provide more precise balancing B. produce a higher power factor C. eliminate arcing between the stator and the frame D. provide a means for starting

Last Answer : Answer: D

Description : The purpose of amortisseur windings in a synchronous motor is to ______________. A. reduce eddy current losses B. produce a higher power factor C. provide a means for starting D. eliminate arcing between the stator and the rotor

Last Answer : Answer: C

Description : A damper winding is designed as part of a synchronous motor to ____________. A. increase efficiency B. provide starting torque C. provide excitation D. eliminate slippage

Last Answer : Answer: B

Description : The function of amortisseur, or damper windings in a synchronous motor is to _____________. A. eliminate slippage B. provide excitation C. provide starting torque D. increase efficiency

Last Answer : Answer: C

Description : A low-voltage protection circuit is used in electric motor starting equipment to _____________. A. trip circuit contactors when the motor overspeeds due to low voltage B. trip circuit ... voltage without manually resetting D. prevent the motor from restarting automatically on restoration of voltage

Last Answer : Answer: D

Description : The function of damper windings in a synchronous motor is to _____________. A. eliminate slippage B. provide excitation C. provide starting torque D. increase efficiency

Last Answer : Answer: C

Description : Amortisseur windings are installed in a synchronous motor to _____________. A. reduce eddy current losses B. produce a higher power factor C. provide a means for starting D. eliminate arcing between the stator and the rotor

Last Answer : Answer: C

Description : The main purpose of the auxiliary winding on a split-phase, single-phase motor is to _____________. A. limit the starting voltage B. increase the starting current C. start the motor D. keep the motor running in the event the main winding should fail

Last Answer : Answer: C