ppt.pptx
- 1. Fully Automatic Star Delta Starter
- 2. STAR DELTA A star delta starter is the most commonly used method for the starting of a 3 phase induction motor. In star delta starting an induction motor is connected in through a star connection throughout the starting period. Then once the motor reaches the required speed, the motor is connected in through a delta connection. Presentation title 2
- 3. Fully automatic Star delta starter working principle There are many different starting methods are used to start a three-phase induction motor like Star delta starter. One of them, popular and cheapest is aDirectonlinestarter. But its use limited for smaller HP motor, to start higher rating 3 phase motors star-delta starter is used. wye-delta starter is useful where all six terminals of themotorare accessible. In this article, we will discuss star delta starter working principle with help of power and control diagram. Presentation title 3
- 4. Star-Delta starter is the simplest starting method for reducing the inrush starting current of the Induction motor. The starter can be used with all squirrel-cage induction motors that are delta-connected for normal operation. The reduction of the high motor current causes a reduction of the starting torque of the motor. Star-delta starting is therefore especially suitable for drives that are not loaded until after starting. The starting time is longer than with direct starting, which is especially apparent when driving larger inertial masses. To start a large motor, we need a reduced voltage starter,to limit starting current. Star delta starter is a reduced voltage starter that applies 1/√3 voltages during the starting time
- 5. The photographic view of star delta starter Presentation title 5
- 6. Application of Star Delta Starter Presentation title 6 • The star-delta method is usually only applied to low to medium voltage and lightstarting torque motors. • The received starting current is about 30 % of the starting current during direct on linestart and the starting torque is reduced to about 25 % of the torque available at a • D.O.L start. • This starting method only works when the application is light loaded during the start. • If the motor is too heavily loaded, there will not be enough torque to accelerate themotor up to speed before switching over to the delta position
- 7. Component Details: Contactor Contactor Components: The following three are crucial components of the contactor: 1. Coil or Electromagnet 2. Enclosure 3. Contacts “ ”
- 8. Contactor Components Presentation title 8 1. Coil or Electromagnet: This is the most crucial component of a contactor. The driving force that is required to close the contacts is provided by the coil or electromagnet of the contactor. The coil or electromagnet and contacts are protected by an enclosure. 2. Enclosure: Just like the enclosures used in any other application, contactors also feature an enclosure, which provides insulation and protection from personnel touching the contacts. The protective enclosure is made from different materials, such as polycarbonate, polyester,Nylon 6, Bakelite, thermosetting plastics, and others. Generally, the open-frame contactor features an additional enclosure, which protects the device from bad weather, hazards of explosion, dust, and oil. 3. Contacts: This is yet another important component of this electrical device. The current carrying task of the contactor is done by the contacts. There are different types of contacts in a contactor namely, contact springs, auxiliary contacts, and power contacts. Each type of contact has an individual role to play.
- 9. How the Contactor Operates Presentation title 9 • Operating Principle of a Contactor: •The current passing through the contactor excites the electromagnet. The excited electromagnet produces a magnetic field, causing the contactor core to move the armature. A normally closed (NC) contact completes the circuit between the fixed contacts and the moving contacts. This permits the current to pass through these contacts to the load. When current is removed, the coil is de-energized and opens the circuit. The contacts of the contactors are known for their rapid open and close action.
- 10. Contactor Block The LADN22 is an auxiliary contact block for use with TeSys D and F series contactors. • 2NO + 2NC contact configuration • Rated operational voltage of 690VAC • Minimum switching current of 5mA at 17V • Screw clamp terminals • Compliance to UL and CSA standards Instantaneous auxiliary contacts operation APPLICATIONS:- • Industrial, Power Management, Automation & Process Control, Consumer Electronics Presentation title 10
- 11. Terminal Blocks Terminal Blocks are in stock with same-day shipping at Mouser Electronics from industryleading manufacturers. Mouser is an authorized distributor for many terminal block manufacturers including Amphenol, Cinch, Eaton, FCI, Molex, Phoenix Contact, TE Connectivity, Wurth, & more. A terminal block (terminal strip) is a modular, insulated block which connects one or more circuits to another. The connections are typically made by a screw or clamp lowering onto a bare wire in order to complete the connection. Due to this type of connection, terminal blocksare extremely easy to use and are available in a variety of types across multiple applications. The most common types are barrier, pluggable, fixed, & DIN rail mount. Presentation title 11
- 12. MCB (Miniature Circuit Breaker) As we all know that, all fuses need to be replaced with them for safety and control purposes. MCBs are electromechanical devices which are used to protect an electrical circuit from an overcurrent. It can be reclosed without any hand-operated restoration. MCB is usedas an option to the fuse switch in most of the circuits. Unlike a fuse, MCB does not have to be replaced every time after a failure as it can be reused. Another huge advantage of MCBs is that the detection of a problem is easy. Whenever thereis a fault in the circuit, the switch comes down automatically and we are hereby informed that there was a fault. We can then manually go and put the MCB back up and the electricity will start flowing again.
- 13. A safety device that protects electrical circuits from the effects of excessive currents. A fuse commonly consists of a current-conducting strip or wire of easily fusible metal that melts,and thus interrupts the circuit of which it is a part, whenever that circuit is made to carry a current larger than that for which it is intended. The screw-plug fuse was once commonlyused in domestic electrical systems. It contains a short bit of wire (the fusible element) enclosed in a fireproof container that has a screw-threaded base; the wire is connected to metal terminals at both the screw base and at the side, and the whole is covered with a transparent glass or mica window for seeing whether the fuse has melted. The cartridge fuse,a type of fuse widely used in industry where high currents are involved, has a fusible element connected between metal terminals at either end of a cylindrical insulating tube. Presentation title 13 GLAS S FUSE The photographic view of glass fuse.
- 14. TIMER • Time delay relays are simply control relays with a time delay built in. Their purpose is to control an event based on time. The difference between relays and time delay relays is when the output contacts open & close: on a control relay, it happens when voltage is applied and removed from the coil; on time delay relays, the contacts can open or close before or after some time delay. • Typically, time delay relays are initiated or triggered by one of two methods: • application of input voltage • opening or closing of a trigger signal Presentation title 14
- 15. The photographic view of timer. These trigger signals can be one of two designs: • a control switch (dry contact), i.e., limit switch, push button, float switch, etc. • voltage (commonly known as a power trigger To help understand, some definitions are important: • Input Voltage-control voltage applied to the input terminals. Depending on the function, input voltage will either initiate the unit or make it ready to initiate when a trigger is applied. • Trigger Signal-on certain timing functions, a trigger is used to initiate the unit after input voltage has been applied. As noted above, this trigger can either be a control switch (dry contact switch) or a power trigger (voltage). • Output (Load)-every time delay relay has an output (either mechanical relay or solid state) that will open & close to control the load. Note that the user must provide the voltage to power the load being switched by the output contacts of the time delay relay. Presentation title
- 16. 2CO RELAY DPDT stands for the double-pole double-throw relay which is an electromagnetic device used to separate two circuits electrically and connect them magnetically. They are often used to interface an electronic circuit, which works at a low voltage to an electrical circuit which works at a high voltage. The photographic view of 2CO relay.
- 17. 4CO RELAY 4CO Relay generally called 14pin relay. This type relay having 4 position change contacts generally called NO, points. In this relay coil voltage is 230V AC and 30v DC. It having 4 common points change their position from the initial stage. Contacts rating depends on the demand by user The photographic view of 4CO relay.
- 18. PUSH BUTTON Push Buttons（Type：Illumination push-button） Push buttons open and close contacts by force applied by the finger to the operating component in the vertical axis direction. Push buttons consist of the operational component that transfers external force to the switch, the switching component that opens and closes the electrical circuit, the mounting component that grounds the switch and fixes it to the panel, the light source that indicates operational status, and the casing that protects the interior components. LED illuminated push buttons come with the LED light source that is built into the operational part and cannot be taken out; push buttons with incandescent lamp illumination have independent operational parts and light source that can be separated. Nonilluminated types do not come with a light source. Button light colours include green, red, orange, etc. Switch function styles include momentary, where the pressed button returns to the initial position once it is released, alternate action, where the first push maintains the operational position, which is then disengaged with a second push, etc. Presentation title The photographic view of push button.
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