2. For which motors DOL starter can be used? Explanation: DOL starters are limited to the small rating motors where distribution system (mains supply) can withstand high starting currents without excessive voltage dips.
For which motors DOL starter can be used?
Direct On Line Motor Starter (DOL) is suitable for:
- A direct on line starter can be used if the high inrush current of the motor does not cause excessive voltage drop in the supply circuit. …
- DOL starting is sometimes used to start small water pumps, compressors, fans and conveyor belts.
What is the maximum rating of motor DOL starter can be used Mcq?
Direct-on-line (DOL) starting are not used for large DC motor because the starting current will be enormously high which will cause large voltage drop in the supply mains and armature may get damaged due to excessive heating. It is used for starting of induction motor of ratings up to 3.75 KW. 04․
Which motor is used in DC drive Mcq?
The Ward-Leonard system consists of a fixed speed 3-phase AC induction motor driving by a separately excited DC generator that, in turn, feeds a variable voltage to a shunt wound DC motor. So this is essentially a DC variable speed drive.
Which motor is used for high starting torque application Mcq?
Thus, DC series motor is used in conveyors as it provides very high starting torque, which is practically 5 times the rated torque.
What is the full form of DOL starter?
A direct on line (DOL) or across the line starter applies the full line voltage to the motor terminals. This is the simplest type of motor starter. A DOL motor starter often contains protection devices (see below), and in some cases, condition monitoring.
Why is DOL starter used up 5 hp?
Direct-on-Line (DOL) Starter
This heavy current reduces as the motor accelerates to its rated speed. … For a large rating motor, ranging from 5 HP to 25 HP, oil immersed DOL starters are used which provides insulation against sparking on contact points and hence increases the life of starter.
What are the types of starter?
Types of Magnetic Motor Starters
- Direct-On-Line Starter. The direct-on-line starter is the simplest form of motor starter, other than a manual starter. …
- Rotor Resistance Starter. …
- Stator Resistance Starter. …
- Auto Transformer Starter. …
- Star Delta Starter.
Which motor is more efficient Mcq?
Two pole motor has better efficiency. Two pole motor has better rpm and noise performance.
Which motor is used in tramway?
Dc motor (Ma) and induction motor (Mc) are currently manufactured and used in 105 N tram drive, their parameters are available. Dc motor (Mb), brushless motor (Me) and slip-ring motor (Md) pa- rameters have been determined by analysis.