Перевести текст: Electrical equipment includes any machine powered by electricity. It usually consists of an enclosure, a variety of electrical components, and often a power switch.
I. Electrical motors are one of the most common items of electrical equipment in service today. The motor or an electrical motor is a device that has brought about one of the biggest advancements in the fields of engineering and technology ever since the invention of electricity. A motor is nothing but an electro-mechanical device that converts electrical energy into mechanical energy. It's because of motors, life is what it is today in the 21st century. Without the motor, we had still been living in Sir Thomas Edison’s Era where the only purpose of electricity would have been to glow bulbs. There are different types of motor have been developed for different specific purposes. In simple words, we can say a device that produces rotational force is a motor. The very basic principle of functioning of an electrical motor lies on the fact that force is experienced in the direction perpendicular to magnetic field and the current, when field and current are made to interact with each other.

Electric motors are broadly classified into two categories as follows:

AC Motors and DC Motors.

The primary classification of motor or types of motor can be tabulated as shown below.

The DC motor is of vital importance for the industry today and is equally important for engineers to look into the working principle of DC motor in details. To understand the operating principle of DC motor we need to first look into its single loop constructional feature. The very basic construction of a DC motor contains a current carrying armature, connected to the supply end through commutator segments and brushes. The armature is placed in between north pole and south pole of a permanent or an electromagnet. As soon as we supply direct current in the armature, a mechanical force acts on it due to the electromagnetic effect of the magnet on armature conductors.

II. A pump is a device that moves fluids (liquids or gases), or sometimes slurries, by mechanical action. Pumps can be classified into three major groups according to the method they use to move the fluid: direct lift, displacement, and gravity pumps.

Pumps operate by some mechanism (typically reciprocating or rotary), and consume energy to perform mechanical work moving the fluid. Pumps operate via many energy sources, including manual operation, electricity, engines, or wind power, come in many sizes, from microscopic for use in medical applications to large industrial pumps.

Mechanical pumps serve in a wide range of applications such as pumping water from wells, pond filtering and aeration, in the car industry for water-cooling and fuel injection, in the energy industry for pumping oil and natural gas or for operating cooling towers.

When a casing contains only one revolving impeller, it is called a single-stage pump. When a casing contains two or more revolving impellers, it is called a double- or multi-stage pump.

Pumps are divided into 2 major categories: dynamic and positive displacement. Centrifugal pumps are the most used pump type in the world, due to simple working principle and relatively inexpensive manufacturing cost. An increase in the fluid pressure from the pump inlet to its outlet is created when the pump is in operation. This pressure difference drives the fluid through the system or plant.

Submersible pumps (also known as storm water pumps, sewage pumps, septic pumps) can still operate when being fully submerged in water.

ответьте на вопросы.

1. What do you understand under the term «electrical equipment»?

2. What is an electric motor?

3. What is the very basic principle of functioning of an electrical motor?

4. What types of motors do you know?

5. What are drives and their functions?

6. What is a pump?

7. How does a pump work?

8. What main types are all pumps divided into?

ValiahmetovaKa    2   19.04.2021 11:53    4