Sunday, October 18, 2015
Saturday, October 17, 2015
Friday, October 16, 2015
Wednesday, October 14, 2015
Tuesday, October 13, 2015
Thursday, September 10, 2015
Electrical Wire Size Table
Wire size is most important aspect in electrical department. Small wire size may leads to overload current and cause short circuit in circuit.
In order to prevent this there is table in terms of wire size and ampere current in wire.High current needs high gauze wires inorer to withstand current within it.
Suppose we have 3 phase induction motor load so we need a wire relative to ampere labeled on motor.
Tuesday, September 8, 2015
Monday, September 7, 2015
Principle of Working of DC Motor
Principle:-
A DC motor principle is just to convert Electrical energy in Mechanical Energy.
As shown in figure, an armature is kept between magnetic field generated by 2 magnets.An armature is connected to commutator, brushes with DC supply as shown in fig.
Fleming's Left hand thumb Rule :-
According to Fleming's Left hand thumb Rule,when a current carrying conductor is kept between magnetic field,then conductor experience force in the direction perpendicular to the magnetic field.
Thus here in DC motor,an armature experience force perpendicular to magnetic field as soon as current passes through it due to DC supply given as shown in fig.
HMI (Human Machine Interface)
HMI means Human Machine Interface a touch screen compact electronic equipment which controls industrial processes at a same time.
On HMI the user can view current data,log its data in .CSV file,control connected equipments connected with it.HMI used RS 485 Half wave / Full wave communication I.e 3 wire/5 wire communication.
RS485 Half Duplex/3 wire:-
In this the user cab only read data from the field, can't control it as the data come one way from field only.
Rs485 Full Dulpex:-
In this the user can read as well as write data I.e User can view data from the field and also controls it due to 2 way communication I.e Full Duplex
Uses:-
HMI are generally used in production, manufacturing, Power Plant, Dairy Plant,Automation, Control Panels,Packaging Machines, HVAC system I.e Heat Ventilation & Air Conditioning system,Solar Power Plants,Chemical Mixing Plant,Printing Industry etc.
Push Button
In Automation, Electronic, Electrical, etc or any other industry Pushbutton is very important .
Pushbutton has 2 terminals phase & Neutral.Normally pushbutton is open I.e NO (Normally Open),On presssing it Contact touches each other and allow current to pass through it,Spring Mechanism inbuilded in it,thus on releasing Pushbutton again it Normally Opens
MCCB (Moduled Case Circuit Breaker)
A circuit breakeris an automatically operatedelectricalswitchdesigned to protect anelectrical circuitfrom damage caused byoverloadorshort circuit.
Its basic function is to detect a fault condition and interrupt current flow. Unlike afuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation. Circuit breakers are made in varying sizes, from small devices that protect an individual household appliance up to largeswitchgeardesigned to protecthigh voltagecircuits feeding an entire city.
Sunday, September 6, 2015
Working of Relay
The diagram shows an inner section diagram of a relay. An iron core is surrounded by a control coil. As shown, the power source is given to the electromagnet through a control switch and through contacts to the load. When current starts flowing through the controlcoil, the electromagnet starts energizing and thus intensifies the magnetic field.
Thus the upper contact arm starts to be attracted to the lower fixed arm and thus closes the contacts causing a short circuit for the power to the load. On the other hand, if the relay was already de-energized when the contacts were closed, then the contact move oppositely and make an open circuit.As soon as the coil current is off, the movable armature will be returned by a force back to its initial position.
This force will be almost equal to half the strength of the magnetic force. This force is mainly provided by two factors. They are the spring and also gravity.Relays are mainly made for two basic operations. One is low voltage application and the other is high voltage. For low voltage applications, more preference will be given to reduce the noise of the whole circuit. For high voltage applications, they are mainly designed to reduce a phenomenon called arcing
Line choke
A line choke is used to provide better protection against overvoltages on the line supply and to reduce the harmonic distortion of the current produced by the drive.
Saturday, September 5, 2015
Subscribe to:
Posts (Atom)