Resistance Temperature Detectors (RTD)
as the name implies, are sensors used to measure temperature by correlating the resistance of the RTD element with temperature.
RTDs are relatively immune to electrical noise and therefore well suited for temperature measurement in industrial environments, especially around motors, generators and other high voltage equipment.
Type
Pt 100, 200, 500, 1000,
copper 50,53. etc
Element size (MI)
Wire wound ceramic encapsulated
Wire wound Glass encapsulated
Thin film ceramic encapsulated
Connection
2, 3, 4 wire
Accuracy
Class A, B 1/2, 1/3, 1/5, 1/10 DIN
When a battery is connected to a series resistor and capacitor, the initial current is high as the battery transports charge from one plate of the capacitor to the other. The charging current asymptotically approaches zero as the capacitor becomes charged up to the battery voltage. Charging the capacitor stores energy in the electric field between the capacitor plates.
Shockley diodes are curious devices, but rather limited in application. Their usefulness may be expanded, however, by equipping them with another means of latching. In doing so, each becomes true amplifying devices (if only in an on/off mode), and we refer to these as silicon-controlled rectifiers, or SCRs.
The progression from Shockley diode to SCR is achieved with one small addition, actually nothing more than a third wire connection to the existing PNPN structure
A vacuum circuit breaker is such kind of circuit breaker where the arc quenching takes place in vacuum. The technology is suitable for mainly medium voltage application. For higher voltage Vacuum technology has been developed but not commercially viable. The operation of opening and closing of current carrying contacts and associated arc interruption take place in a vacuum chamber in the breaker which is called vacuum interrupter. The vacuum interrupter consists of a steel arc chamber in the centre symmetrically arranged ceramic insulators. The vacuum pressure inside a vacuum interrupter is normally maintained at 10 – 6 bar.
It depends what circuit you are making.
Circuit breakers come in different 'ratings' and so are chosen according to the power demands of the circuit you have.
You don't choose a circuit for a circuit breaker as such, you choose a circuit breaker according to what circuit you have made.
There are several type of circuit breakers now a day we are using these are as follows:
1. M.C.B. (Miniature circuit Breaker)
Rating : 1, 2, 4, 6, 10, 16, 20, 25, 32, 63 Amperes
2. M.C.C.B. (Molded case circuit Breaker)
Rating : 10, 16, 20, 25, 32, 63, 100, 200, 250, 400 Amperes.
3. A.C.B. (Air Circuit Breaker)
Rating : 400, 800, 1000, 1200, 1500, 1800, 2000 Amperes.
4. A. B. Switch (Air Breaker)
used in High tension line.
5. SF6 Breaker (Contact break in the Sf6 medium)
used in High tension line.
mcb internal circuit shown in figure ....
What is a Solenoid Valve? How does a Solenoid Valve Work?
Solenoid valves are electrically actuated mechanical systems that control the flow of substances like liquids and gases. Solenoid valves are commonly used on automotive transmissions.The solenoid valve uses an electric current which moves the solenoid. This pulls a piston preventing it from stopping the flow of air and fluid. The valve will need a constant flow of electrical current to remain open because when there is no current flow, the electromagnetic field scatters and the valve returns to its original position.
An AC series motor is a special type of motor, which has been designed to operate on either AC or DC power. This type of motor is also called universal motor. An advantage of the AC series motor is, this type of motor is designed to provide high starting torque and as it has very compact design so high running speeds are produced. The basic construction of an ac series motor slightly differs from the construction of a dc series motor. AC series motor has low speeds for large loads and high speeds for light loads. This type of motor is widely used in small home appliances like blower, grinder and power tools like drill machine etc.
