Wire wound adjustable resistors or rheostats are high power rheostats that can provide variable resistances to the circuit over a certain range. Hence, these are widely used in those areas where circuits are often required to work at high temperatures. It differs from the potentiometer in terms of power handling capacity and construction. The outer appearance of a wire wound rheostat gives an impression of a hollow cylinder having two thin lead connections at the sides of its terminal and a horse shoe shaped metal slider that has a nut bolt assembly at its open end. The ceramic and the wire wound assembly over it are covered by silicone. This coating ensures that the rheostat is tolerant to temperature variations, moisture, and oil and is very well electrically insulated. A lead wire wounded on the ceramic rod serves as the variable resistor.
Insight – How Number Combination Lock works
Number combination lock is like a mystery game of combinations and sequences. With the use of mathematical logics and basic laws of physics (balancing of forces) the old traditional padlocks have been replaced by new and modified number combination lock. Padlocks are the portable locks that were designed to defend against any theft, vandalism or sabotage but with passage of time they became part of day to day life as a safety measure. Padlocks used earlier were heavy and required key to unlock but with number combination lock it becomes easy to handle the system as only thing that is required is a code which can activate or deactivate the lock. Now, all one has to do is set their code and activate the lock. Let’s take the insight of number combination lock in the following section stepwise from its outer parts to the innermost components.
Insight – How Polyester Capacitor works
Working of capacitors often gets restricted due to losses such as leakage loses or surge shocks. While leakage loses can be reduced through proper insulation through an epoxy or ceramic coating, damage due to short circuits can be avoided only when the metal plates aren’t eroded due to high current. At surge voltages, while capacitors such as ceramic break down and lose their ability to store charge metalized film capacitors can repair themselves.Whenever high voltage is across the capacitor, instead of breaking down, the metal on the film gets perforated. The high voltage in turn also heats the dielectric film which expands and fills the part where perforation occurred. This increases the longevity of the capacitor, thus improving the working of the circuit.
Insight – How Trimmer Capacitor works
A trimmer or preset is a miniature adjustable electrical component. Trimmers can be variable resistors (potentiometers), variable capacitors, and trimmable inductors. They are common in precision circuitry like A/V components, and may need to be adjusted when the equipment is serviced. Unlike many other variable controls, trimmers are mounted directly on circuit boards, turned with a small screwdriver and rated for many fewer adjustments over their lifetime. Trimmers like trimmable inductors and trimmable capacitors are usually found in superhetrodyne radio and television receivers, in the Intermediate frequency, oscillator and RF circuits. They are adjusted into the right position during the alignment procedure of the receiver. Trimmers come in a variety of sizes and levels of precision; for example, multi-turn trim potentiometers exist, in which it takes several turns of the adjustment screw to reach the end value, allowing for very high degrees of accuracy.
Insight – How Ethernet Cable works
If you ever connected a PC with a broadband connection you surely used an Ethernet cable to do it. Ethernet cables also called LAN cables or Cat 5 cables are often used in home networks. They are categorized into two types – Straight through and Crossover cables. Straight though cables are used to connect different types of devices (like PC to Hub) whereas Crossover cable is used to connect same type of devices such as PC to PC or Switch to Switch. Both the cables are almost identical except the wiring scheme of their end connectors. Depending on the type of the cable, straight through or crossover, both end connectors either have same or different types of wiring schemes, respectively. The connector consists of a mechanical lock which aids it to fix the cable in the port. Once a cable is thoroughly plugged into the device port a click sound is produced.
Insight – How Resistor works
Resistors are one of the most crucial parts of any circuit. They vary from micro-ohms to mega-ohms in terms of their value. Also, they come in various forms like embedded as a chip in an IC, can be a bare metal or can be in form of a conductive plastic. This Insight will give a detailed exploration of carbon film resistor which has a ceramic core. Resistor looks like a solid capsule with leads at both ends which are used to connect it to the circuit. It is interesting to know that the temperature coefficient is in ppm instead of being in °C . This can be explained using a simple example. Consider a resistor with a rating 30 ppm for its temperature coefficient. This means that for every 1°C rise in temperature, the resistance would not change more than 30/10000000 or 0.000030 ohms.
Insight – How Desoldering Pump works
DESOLDERING is the process of removing soldered components from a circuit made on PCB. Desoldering pump along with the soldering iron is used for this purpose. A desoldering pump also known as solder sucker is a small mechanical device which sucks the liquid/molten solder from the joint where the components are mounted. In order to desolder a component from the PCB, we first heat up the solder joint with the soldering iron till the solder liquefies/melts. At the same moment we actuate the soldering pump by pressing the trigger lever and bring the tip over the molten metal and pull the trigger back by pressing a button shown in the below image. At this instant the lever is pulled back and the tip of the pump sucks the molten solder. This process is repeated until all the residue solder is sucked by the pump and the hole on the PCB is clear to solder a fresh component.
Insight – How Geared DC Motor works
Geared DC motors can be simply put as an extension of DC Motor. The speed of the motor is counted in terms of rotation of the shaft per minute and is termed as RPM .Simple DC motors are restricted in terms of power and lack proper speed control. They can even run at speeds approximately close to 3,000 RPM which might get beyond the desired requirements of the user. However, using a geared motor can reduce down the RPM such as 150 and lower, hence providing more torque to the machine. This concept where gears reduce the speed of the vehicle but increase its torque is known as gear reduction. This Insight will explain those major as well as minor details that make the gear head and hence the geared DC motor work.
Insight – How MCB works
MCBs or Miniature Circuit Breakers are electromechanical devices which protect an electrical circuit from an overcurrent. The overcurrent, in an electrical circuit, may result from short circuit, overload or faulty design. An MCB is a better alternative to a Fuse since it does not require replacement once an overload is detected. Unlike fuse, an MCB can be easily reset and thus offers improved operational safety and greater convenience without incurring large operating cost. The principal of operation is simple. An MCB functions by interrupting the continuity of electrical flow through the circuit once a fault is detected. In simple terms MCB is a switch which automatically turns off when the current flowing through it passes the maximum allowable limit. Generally MCB are designed to protect against over current and over temperature faults (over heating).
Insight – How Digital Thermometer works
Digital Thermometers are slowly replacing the conventional mercury thermometer due to the ease of taking reading. People often have the misconception that it contains mercury. Digital Thermometers are mercury free. These thermometers contain thermistor inside the tip which is used to measure the temperature. They provide quick and highly accurate results over the body temperature range. These thermometers are easy to read with LCD display on them. They are equipped with beep alarm & memory function and can record a wide range of temperature. Doctor’s thermometer which are mostly used can read temperature between 94oF and 105oF (35oC and 42oC). It is three in one thermometer as it can record oral, auxiliary and rectal temperatures.
Insight – How Mercury Thermometer works
A thermometer is an instrument that measures the temperature of a system. The word Analog thermometer refers to mercury thermometers commonly used in homes and clinics to measure body temperatures. The mercury used in thermometer is silvery white in color and in liquid state. Mercury is one of the 92 naturally occurring elements that become liquid at room temperature and remains in liquid state throughout a wide range of temperature. Basal thermometers are ultra sensitive thermometers and they can track body’s minutest temperature shift i.e. they can accurately measure the temperature shift by 0.1 degrees Fahrenheit. On the other hand oral thermometers can measure a minimum temperature shift of 0.2 degrees Fahrenheit. Oral thermometers are used to measure the body temperature at the time of fever while basal thermometers are used by females to chart their basal body temperature to predict their fertile period or ovulation.
Insight – How Electronic Ballast works
Electronic ballasts are gradually replacing conventional magnetic ballasts (commonly known as choke) from the fluorescent tubes. They have higher efficiency as compared to magnetic ballasts and provide a flicker free start up to the tube. Also it does not produce the ‘hum’ sound which is very annoying with the magnetic ballastElectronic ballast uses semiconductor components and operates at 20 KHz-80KHz unlike the magnetic ballast which operates at 50 -60 Hz. At high frequency the lamp requires less input power, thereby increasing the efficiency. When power supply enters in to the ballast circuit, it first goes through an EMI filtration to block the ballast generated noise. Capacitors are used for the same.
Insight – How Fan Regulators work
Fan regulators have an important place in the electrical switch boards. Fan regulators are very similar to light dimmers. Their function is to regulate/control the speed of the fan and provide a convenient environment for the residents. The traditional regulators which are bulky use a resistance having taps and connected in series with the fan. When we move the knob different amount of resistance gets inserted in the circuit. Although cheap the biggest problem with such a regulator is that a considerable amount of energy is lost in form of heat through the resistance. When the fan is operating at low speed the power loss is significant. The technologically superior electronic regulators overcome these problems by using electronic components to control the speed of the fan.
Insight – How Ding Dong Doorbell works
The ding dong sound of the doorbells signifies the presence of someone at the door. Although there are many doorbells available in the markets today with a variety of sounds, the ding dong doorbell still has its share of the market. What makes them interesting is how do they produce this ding dong sound?The ding dong doorbells use the magnetic force produced by an AC solenoid to force an iron rod (called the plunger) to hit against aluminum sheets placed at both sides of the solenoid. This in turn produces the ding dong sound. The DC and AC solenoids are different. The doorbell uses an AC solenoid. When current flows thorough the coil of an AC solenoid, a magnetic field is produced. This magnetic field produces a magnetic force and pulls the plunger in its direction.
Insight – How Earphone works
Earphones/Earbuds have been assisting mobile gadgets since the invention of walkman. Though they account for hardly a few percentage of the cost of the entire device but their evolution over the time has never been an easy challenge for the engineers. Shape, size, comfort and sound quality are the key parameters while designing an earphone. From morning walk to making long journeys pleasant, ear phones cannot be kept out of the daily life.Technically speaking earphones falls in the category of transducers that convert electrical energy into sound energy. Undoubtedly, over the years companies have been adding more and more complex features in the earphones to improve the listening experience of the users. In this article we will explore more about the earphones.
Insight – How Ball Pen works
The history of Ball pen dates back to 1880s. It was John Loud who received the first patent on Ball pen. Technically speaking ball pen is a device, which when rubbed on a paper leaves a permanent continuous colored mark following the direction of the motion. Ball pens are available in various size, shapes, colors and prices varying from almost a few cents to few hundred dollars and even more. Researchers have been working continuously to improve the performance of the pens. Some important performance parameters include the grip, the tip of the pen and controlling the ink flow for longer life. Manufacturers produce ball pen in different shape, size and color. A plastic or a metal casing encapsulates the entire assembly. The tip of the pen is kept inside the outer casing by means of mechanical arrangements when it is not used. Broadly classifying the ball pens are available in two forms disposable or reusable.
Insight – How Lithium-coin batteries work
A Lithium coin battery is a sub category of primary batteries. The name is derived from the shape which resembles a coin. Both the types i.e., disposable and rechargeable are available in the market in a variety of sizes. Some common applications are wrist watches, calculators, hearing aids, RTC, sensors, motherboard (to keep the time and date updated), memory units etc. The battery used in this article is disposable type. The key chemical constituents are Lithium, Manganese oxide and an organic electrolyte. The voltage range for these types of batteries varies from 1.5V to 3.7 V. When used in a device or to power an electronic circuit the polarities should be properly taken care of else it may result in distortion, leakage, overheating, explosion or fire thereby damaging the device.
Insight – How Pencil Cell, Primary, Carbon-Zinc Battery works
Carbon Zinc battery also known as primary cell or dry cell or pencil cell is among the cheapest reliable power sources powering a large variety of electronic equipments since the last century. It is used to provide a constant voltage source through a chemical reaction. This battery cannot be recharged and has to be disposed after usage. A commonly used primary battery is shown in the image above. These types of batteries are available in various sizes and are used to power devices like Torches, Toys, Remote Control, Clocks etc. The battery has two terminals the top view is the positive terminal and the bottom view is the negative terminal.
Insight – How Pendrive works
USB Flash Drives or commonly called as Pen Drives are popular removable storage media having a storage capacity up to 256 GB. They are preferred over the other conventional storage devices like floppy disks or CD ROMs as they are faster, smaller and have a longer life span. The internal circuitry of the pen drive draws power from the computer for its operation. They have an integrated USB interface to communicate with the computer. The important parts of the pen drive are USB connector, crystal oscillator, memory chips and a controller to interact with the PC. The pen drive used here has storage capacity of 4GB.
Insight – How Floppy Disk works
Floppy disk, another interesting invention of the computer age is a storage device used to store and carry data. Although obsolete now a days, it has been replaced by technologically superior storage media like CD, DVD, Pen drive, portable hard disc etc. Historically this technology was dominant in the markets for more than two decades. Floppy disks are commonly identified by their sizes. The 3.5 inch disk with a maximum capacity of 1.44MB was the most commonly used floppy. The data inside a floppy is magnetically stored on a thin plastic sheet which is coated with iron oxide. It is commonly called as magnetic disk.