

Switching and linear regulator use fundamentally different techniques to produce a regulated output voltage from an unregulated input.Each technique have advantages and disadvantages.So the application will determine will determine the moist suitable choice. Linear power supplies can step-down an input voltage to produce a lower output voltage.This is done by operating a bipolar transistor or…

A recorder is a measuring instrument that display a time varying.Signal in a form easy to examine and re-examine,perhaps long after the original signal has ceased to exist.In other word a recorder is a device whose function is to record the value of quantity as it is being measured.Such device may include graphic recording devices,computer…

In the year 1974 B.C.C.L introduced a payroll system which used the computer concept.Subsequently the computerization was introduced for ledger,relative reports etc.In the year 1982 first computer was installed at Kalyan Bhawan from Calcutta for data processing.Till now the Headquarters of B.C.C.L has been centralized through networking.Each area of B.C.C.L  has its own EDP department of data processing. COALNET…

Bharat Coking Coal Limited is a subsidiary of Coal India Limited,Government of India Enterprise,mainly situated in the state of Jharkhand & partly in West Bengal.It is the largest coal company operating in the Jharia coalfields & is the prime source of coking coal in the country. The management of the coking coal mines in Jharia…

In practice two types of impulse voltages can occur (i) full wave and (ii) chopped impulse wave.If the lightning surge travels along the transmission line,it results in full wave impulse voltage reaching to transformer.Whereas if the surge voltage causes a flash over just before reaching to transformer it results in chopped impulse wave. The full…

The zero-power factor characteristic (ZPFC) of an alternator is a curve of the armature terminal voltage per phase plotted against the field current obtained by the operating the machine with constant rated armature current at synchronous speed and zero lagging power factor.The ZPFC is some times called potier characteristic after its originator. For maintaining very…

In an a.c. machine,any flux set up by the load current which does not contribute to the useful flux of the machine is a leakage flux.The effect of the leakage flux is set up a self-induced emf in the armature windings. The leakage fluxes may be classified as follows: 1.Slot leakage 2.Tooth head leakage 3.Coil-end…

CAD has the following advantage over traditional method of design- (i)Â Computer aided design (CAD) is faster and more accurate results than conventional methods. (ii)Â Developing the design of component and associated drafting is a very easy task with CAD. (iii)Â Manipulation of various dimensions,attributes and distance of drawing elements,is very easy.This make CAD the most useful designing…