Knowledge in Gears

Power Transmission.

This document consists of introduction and description on belt drives. Open belt length derivation. Cross belt length derivation. Velocity ratio derivations. Introduction to gears, types of gears and description. Derivations. Numerical problems on belt length, velocity ratio and gears.

Spur Gear Notes (KOM), Gear trains.

A notes on Spur Gear, Gear Trains of Kinematics of Machinery and Theory of Machines.

SWITCH GEAR AND PROTECTIVE DEVICES

Protective Devices: Philosophy of protection, Nature, Causes and consequences of faults, Zone of protection, Requirements of a protective scheme, Basic terminology components of protection scheme. Relay classification, Principle of different types of electromagnetic relay. General equation of phase and magnitude comparators, Duality of comparators, Electromagnetic relays, over current relays Directional relays, Distance relay- impedance, Reactance and Mho type, Differential relays. MODULE-II (10 HOURS) Feeder: Protection: Over current and earth fault protection, Distance protection, Pilot wire protection, Carrier current protection. Generator Protection: Biased differential protection, restricted earth fault protection, Field suppression, Negative sequence protection, Earth fault detection in rotor circuit Power transformer Protection: Biased differential protections, restricted earth fault protection, Buchholz relay Protection of combined transformer and alternator. Bus Zone Protection: frame leakage and circulating current scheme-use of Translay relay. MODULE-III (10 HOURS) Circuit Breakers: Formation of arc during circuit breaking. Characteristics of electric arc. Theories of arc Interruption. Recovery and restriking voltage, interruption of capacitive and inductive currents. Current chopping. Principle of A.C. and D.C. circuit breaking requirements of good circuit breaker circuit breaker rating. Different types of circuit breakers. Air break and Air blast circuit breaker. Plain break and controlled break all circuit breakers. Minimum oil circuit breakers. Vacuum circuit breaker, SF6 circuit breaker. D.C. Circuit breaker. H.R.C. Fuse: Construction and characteristics MODULE-IV (10 HOURS) Static Relays : Development and classification of static relays, Different types of phase and amplitude capacitors, Basic static relays used in protective scheme, Elementary idea about digital & numerical protection. Testing and maintenance of protective gear, Protection against surge-surge absorber, Surge-diverter. Arrangement of Bus bar, Circuit breaker and isolator. Current limiting reactors in power system and their arrangement calculation of fault MVA for symmetrical short circuits. Circuit breaker capacity.

Mechanical Drives and Devices- Gears

The pdf focuses on gears, classification, and types of gears along with their advantages and disadvantages. Helical gears Spur Gear Herringbone Gear, etc are covered in detail in the following pdf. Gear Tooth Failures 1. Wear Failure 2. Bending Failure Gear Lubrication and methods to prevent gear wearing are also covered. The terminology of each of the gears is mentioned in the above PDF.