The Manufacturer

Current Transformer

Current transformers can be used to supply information for measuring power flows and the electrical inputs for the operation of protective relays associated with the transmission and distribution circuits or for power transformers. These current transformers have the primary winding connected in series with the conductor carrying the current to be measured or controlled. The secondary winding is thus insulated from the high voltage and can then be connected to low-voltage metering circuits.

Current transformers are also used for street lighting circuits. Street lighting requires a constant current to prevent flickering lights and a current transformer is used to provide that constant current. In this case the current transformer utilizes a moving secondary coil to vary the output so that a constant current is obtained.

What Are Electrical Insulators?

Electrical insulators, or dielectrics, are materials that can withstand the flow of electrical current. In other words, they are nonconducting materials. They are the opposite of electrical conductors which allow electricity to flow through a material. Insulators help coat, protect, or support electrical conductors so that the electrical current flows through the conductor. These protective materials help prevent electrical shock or sparks.

Dielectric materials are made up of substances with electrons, or energy particles, that are compressed together by chemical process. It is almost impossible to get electrical voltage to pass through these materials. Some insulators are considered to have higher thresholds for electrical voltage than others do, and are aptly called high voltage insulators.

Glass was used as the earliest electrical insulator. Along with other non-metallic materials such as porcelain, mica, and ceramic, glass can withstand the highest volts of electrical current. In the 1800s, this material helped to protect exposed telegraph wiring. Rubber was invented in the mid-1800s, and as an electrical insulator, it was initially applied to portions of the glass insulators used to protect telegraph wiring. Along with plastics, rubber has a lower voltage threshold than glass and porcelain, because of their loose electron composition.

With the advance of telecommunications, Teflon® and silicon dioxide came to be used as electrical insulators to protect exposed wiring. These materials help protect power lines and the internal wiring within transformers and generators.

There are also composite insulators that derive from a mixture of several materials. Composite insulators are suitable for a variety of electrical engineering purposes, ranging from automobiles to appliances. They tend to lack the strength that glass and porcelain has to withstand high electrical voltage and can wear out faster, but they are ideal for a large-scale manufacturing applications because of their low costs and versatility. Porcelain insulators can break easily and can be bulky. Rubber and other composite insulators, also call non-ceramic insulators, are therefore more widely used for engineering purpose.

Screw Compressor

A rotary screw compressor is a type of gas compressor which uses a rotary type positive displacement mechanism. They are commonly used to replace piston compressors where large volumes of high pressure air are needed, either for large industrial applications or to operate high-power air tools such as jackhammers.

The gas compression process of a rotary screw is a continuous sweeping motion, so there is very little pulsation or surging of flow, as occurs with piston compressors.

Rotary screw compressors use two meshing helical screws, known as rotors, to compress the gas. In a dry running rotary screw compressor, timing gears ensure that the male and female rotors maintain precise alignment. In an oil-flooded rotary screw compressor, lubricating oil bridges the space between the rotors, both providing a hydraulic seal and transferring mechanical energy between the driving and driven rotor. Gas enters at the suction side and moves through the threads as the screws rotate. The meshing rotors force the gas through the compressor, and the gas exits at the end of the screws.

The effectiveness of this mechanism is dependent on precisely fitting clearances between the helical rotors, and between the rotors and the chamber for sealing of the compression cavities.

Air Pump

An air pump is a device for pushing air. Examples include a bicycle pump, pumps that are used to aerate an aquarium or a pond via an airstone; a gas compressor used to power a pneumatic tool, air horn or pipe organ; a bellows used to encourage a fire; a vacuum cleaner and a vacuum pump.

The air compressors are the common devices which can increase the amount of air in a particular space. Air pump is used to convert power into kinetic energy. Then the air pressure will be increased. These devices create a force useful for various aspects, from industrial and manufacturing to commercial and personal purposes. 

Air Compressor

An air compressor is a device that converts power (usually from an electric motor, a diesel engine or a gasoline engine) into kinetic energy by compressing and pressurizing air, which, on command, can be released in quick bursts. There are numerous methods of air compression, divided into either positive-displacement or negative-displacement types.

Positive-displacement air compressors work by forcing air into a chamber whose volume is reduced to compress the air. Piston-type air compressors use this principle by pumping air into an air chamber through the use of the constant motion of pistons. They use one-way valves to guide air into a chamber, where the air is compressed. Rotary screw compressors also use positive-displacement compression by matching two helical screws that, when turned, guide air into a chamber, whose volume is reduced as the screws turn. Vane compressors use a slotted rotor with varied blade placement to guide air into a chamber and compress the volume.

 

 

Ignition Coil

An ignition coil (also called a spark coil) is an induction coil in an automobile's ignition system which transforms the battery's low voltage to the thousands of volts needed to create an electric spark in the spark plugs to ignite the fuel. Some coils have an internal resistor while others rely on a resistor wire or an external resistor to limit the current flowing into the coil from the car's 12 volt supply. The wire that goes from the ignition coil to the distributor and the high voltage wires that go from the distributor to each of the spark plugs are called spark plug wires or high tension leads.

Originally, every ignition coil system required mechanical contact breaker points, and a capacitor (condensor). More recent electronic ignition systems use a power transistor to provide pulses to the ignition coil. A modern passenger automobile may use one ignition coil for each engine cylinder (or pair of cylinders), eliminating fault-prone spark plug cables and a distributor to route the high voltage pulses.

Ignition systems are not required for diesel engines which rely on compression to ignite the fuel/air mixture.

Switched-mode Power Supply

A switched-mode power supply (switching-mode power supply, SMPS, or switcher) is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently. Like other power supplies, an SMPS transfers power from a source, like mains power, to a load, such as a personal computer, while converting voltage and current characteristics. Unlike a linear power supply, the pass transistor of a switching-mode supply continually switches between low-dissipation, full-on and full-off states, and spends very little time in the high dissipation transitions, which minimizes wasted energy. Ideally, a switched-mode power supply dissipates no power. Voltage regulation is achieved by varying the ratio of on-to-off time. In contrast, a linear power supply regulates the output voltage by continually dissipating power in the pass transistor. This higher power conversion efficiency is an important advantage of a switched-mode power supply. Switched-mode power supplies may also be substantially smaller and lighter than a linear supply due to the smaller transformer size and weight.

Switching regulators are used as replacements for linear regulators when higher efficiency, smaller size or lighter weight are required. They are, however, more complicated; their switching currents can cause electrical noise problems if not carefully suppressed, and simple designs may have a poor power factor.

Basic Switching Power Supply Design Tutorial

This tutorial was created help you understand switching power supply basics. It applies only to push-pull switching power supplies powered from a 12v DC source (like those used in virtually all car audio amplifiers). It's not an in-depth tutorial and there is much more to learn but this should help introduce you to the basics. Most of the other sites and subject matter seem to be written for those who already know the material. This page is for those who know basic electronics but know absolutely nothing about switching power supplies. Hopefully, the information you find here will help you understand the subject matter well enough to understand the more advanced material you'll find on other sites. If you find that something is being discussed but some pre-requisite information seems to have been omitted, please email me. If you have questions, comments or suggestions regarding this material, feel free to email me.
If you're interested in building a switching power supply but are intimidated by the length of this page, don't be. Take it one section at a time. Give it time to sink in and a couple of days later, read another section.   

The tutorial: 

http://www.bcae1.com/switchingpowersupplydesign/switchingpowersupplytut01.htm

AC/DC Power Adapter

The AC adapter, AC/DC adapter or AC/DC converter is a type of external power supply, often enclosed in a case similar to an AC plug. Other names include plug pack, plug-in adapter, adapter block, domestic mains adapter, line power adapter, wall wart, or power adapter. AC adapters are used with electrical devices that require power but do not contain internal components to derive the required voltage and power from mains power. The internal circuitry of an external power supply is very similar to the design that would be used for a built-in or internal supply.

External power supplies are used both with equipment with no other source of power and with battery-powered equipment, where the supply, when plugged in, can sometimes charge the battery in addition to powering the equipment.

Use of an external power supply allows portability of battery-powered equipment without the added bulk of internal power components and makes it unnecessary to produce equipment for use only with a specified power source.

How Do Lead Acid Batteries Work?

Lead Acid batteries have changed little since the 1880's although improvements in materials and manufacturing methods continue to bring improvements in energy density, life and reliability. All lead acid batteries consist of flat lead plates immersed in a pool of electrolyte. Regular water addition is required for most types of lead acid batteries although low-maintenance types come with excess electrolyte calculated to compensate for water loss during a normal lifetime.

Lead acid batteries used in the RV and Marine Industries usually consist of two 6-volt batteries in series, or a single 12-volt battery. These batteries are constructed of several single cells connected in series each cell produces approximately 2.1 volts. A six-volt battery has three single cells, which when fully charged produce an output voltage of 6.3 volts. A twelve-volt battery has six single cells in series producing a fully charged output voltage of 12.6 volts.

A battery cell consists of two lead plates a positive plate covered with a paste of lead dioxide and a negative made of sponge lead, with an insulating material (separator) in between. The plates are enclosed in a plastic battery case and then submersed in an electrolyte consisting of water and sulfuric acid (see figure # 1). Each cell is capable of storing 2.1 volts.