While PMDC motors are used in hoist, reel and winch applications up to 10 HP, wound field DC motors 14 are commonly used in industrial applications above this range and up to several hundred horsepower (HP), in both the standard and explosion proof types.
What is hoist motor?
The hoist motor as container cranes drive using large energy at the container terminal. Hoist motor of container crane serves to move the spreader in the direction up or down. Worked continuously during loading and unloading operations. The CC hoist motor is the largest motor, mounted on machinery house.
Which DC motor is used in cranes and hoists?
1. Which DC motor is generally preferred for cranes and hoists? Explanation: DC series motor is used where high starting torque is required, thus in cranes and hoists DC series motor is used widely.
Which motor is used in overhead crane?
Conventional AC operated crane drives use slip ring induction motor whose rotor windings are connected to power resistance in 4 to 5 steps by power contactors. Reversing is done by changing the phase sequence of the stator supply through line contactors. Braking is achieved by plugging.
Why DC motor is used in crane?
The starting torque of the DC series motor is proportional to the square of the armature current. … That is why DC series motor is capable to produce high starting torque, and it is preferred for driving heavy loads. The high inertia loads like cranes need a high starting torque. The DC series motor is used in cranes.
What is hoist?
1 : lift, raise especially : to raise into position by or as if by means of tackle hoist a flag hoist the sails Cargo was hoisted up into the ship. 2 : drink sense 1 hoist a few beers. intransitive verb. : to become hoisted : rise let it hoist to the upper deck.
What is chain hoist?
A Chain Block (also known as a hand chain hoist) is a mechanism used to lift and lower heavy loads using a chain. … When the chain is pulled, it winds around the wheels and begins to lift the item that is attached to the rope or chain via a hook.
Which DC motor has maximum self loading property?
Which DC motor has got maximum self-loading property? Explanation: A differentially compound DC motor, flux reduces so sharply at small increase in load at higher values of load. It is advisable that motor should not be used beyond some load value, as it may damage itself by self-loading.
Which power is mentioned on a name plate of a motor?
Which power is mentioned on a name plate of a motor? Explanation: Name plate of the motor shows rated values i.e. rated speed, rated current, rated voltage. It also shows output power available at shaft when all other quantities are set to rated values.
What is a dc series motor?
Series DC motors are a group of self-excited DC motors in which the field coil is connected in series to the armature winding and thus a higher current passes through it. A series DC motor mission is to turn the electrical energy into mechanical one based on electromagnetic law.
Why is the DC motor preferred over AC motor?
AC motors are generally considered to be more powerful than DC motors because they can generate higher torque by using a more powerful current. However, DC motors are typically more efficient and make better use of their input energy.
What is an overhead crane called?
An overhead crane, commonly called a bridge crane, is a type of crane found in industrial environments. An overhead crane consists of parallel runways with a traveling bridge spanning the gap. A hoist, the lifting component of a crane, travels along the bridge.
Which motor is used in watch?
Mini Stepping Motors used in clocks, watches and electric meters are a kind of mechanical-electrical converters, transforming electrical energy to mechanical energy. Mini motors used in different ways are machined by applying different techniques and materials.
Which DC motor is used for the conveyor?
ElectroCraft’s brush or brushless DC motors and gearmotors provide the power, durability and compact size that is required for distributed control of motorized conveyor sections and diverter systems.
Is slip ring induction motor?
A wound-rotor motor, also known as slip ring-rotor motor, is a type of induction motor where the rotor windings are connected through slip rings to external resistance. Adjusting the resistance allows control of the speed/torque characteristic of the motor.
What is the need of 3 point starter?
A three-point starter is an electrical device, used for starting as well as maintaining the DC shunt motor speed. The connection of resistance in this circuit is in series which decreases the initial high current and guards the equipment against any electrical failures.