Elevator/Escalator Study Guide

This study guide is intended to aid applicants who are experienced in the field of electricity /electronics and/or mechanical/hydraulic principles in their preparation for entry-level examinations. By no means is this study guide intended for individuals who have not completed some form of formal technical training through a trade school, college or military training; nor should this guide be used as a sole preparation guide for examination purposes. This guide is divided into three sections: electrical/electronics studies, mechanical/hydraulic studies, and sources of reference material.

Electrical / Electronic Studies

Ohm's Law

  • Demonstrate the ability to perform calculations to determine the unknown electrical quantity when given two of the fundamental values of electricity.

Fundamental Values of Electricity

  • Be well versed with electrical prefixes and have a basic understanding of voltage, current, resistance, and power as well as their units of measurement and abbreviations.
  • Be able to calculate electrical power in watts and combine Ohm's Law and Watt's law to find unknown currents, voltages, resistance, and power.

Basic Instrumentation and Measurements

  • Demonstrate the ability to use common test instruments as well as interpret scale values on digital meters and interpret linear and nonlinear scales on an analog meter.
  • Demonstrate the ability use an oscilloscope and to interpret a waveform pattern, i.e. determine the voltage and frequency using an oscilloscope display. Understand the terminology associated with test instruments.

Basic Electrical Circuits

  • Be able to identify various types of electrical symbols and common circuit devices.
  • Be able to identify various types of resistors and their color code.
  • Understand the relationship of cross-sectional area and length of a conductor as they relate the current in a circuit.
  • Identify the three basic circuit configurations; series, parallel, series-parallel and be able to perform circuit calculations to solve for an unknown electrical quantity, i.e. determine voltage drops, current values, and wattage values.

Sources of Electricity

  • Understand the differences between primary and secondary cells.
  • Distinguish between series and parallel connections.
  • Calculate the outputs of batteries in series and parallel.
  • Identify other sources of electrical energy.

Motors

  • Understand the operation of various dc motors.
  • Understand the operation of three phase motors.

Transformers

  • Understand the operation of a transformer.
  • Identify types of transformer losses.
  • Be able to calculate the various values of currents and voltages in transformer circuits.

Alternating Circuits

  • Be able to calculate various levels of ac voltage, i.e. peak to peak, rms, average.
  • Understand the time relationships of an ac waveform, i.e. quarter-wave, half-wave, full-wave.
  • Understand the difference between direct current and alternating current.
  • Be familiar with reactive components, i.e. capacitors and inductors, and understand how they respond in both a dc circuit and an ac circuit.
  • Be familiar with formulas associated with calculating the transient response time of both an RC and an RL circuit.
  • Understand resonant frequency and how it affects various RCL circuits. Calculate a resonant frequency.

Semiconductors

  • Understand how N-type and P-type materials in a semiconductor conduct electricity.
  • Be able to apply the principles of both forward and reverse biasing.
  • Identify and understand the operation of various types of semiconductor diodes.
  • Understand the operation of a half-wave and full-wave rectifier.
  • Understand power supply filtering.
  • Identify and understand the operation of the bipolar transistor.
  • Identify and understand the operation of several common thyristors.

Digital Circuits

  • Convert decimal numbers to their binary equivalents and binary numbers to their decimal equivalents.
  • Identify various types of logic gates and their associated truth tables.
  • Be able to apply knowledge of basic logic gates to determine the output of a simple logic circuit.
  • Understand the difference between digital and analog devices and their signals. Identify different types of logic families.

Mechanical / Hydraulic Studies

Basic Hydraulics (Fluid Power)

  • Have an overall understanding of hydraulic systems.
  • Be able to apply the principles of Pascal’s Law in analyzing hydraulic systems.
  • Be familiar with Bernoulli’s Principle as it applies to hydraulic systems.
  • Understanding the characteristics of hydraulic fluid.
  • Distinguish the difference between hydraulic fluid and specific gravity.
  • Be aware of the relationship between hydraulic fluid and viscosity.
  • Understand how hydraulic pressure is measured.
  • Realize the purpose of relief valves in a hydraulic system.
  • Realize the purpose of filters in a hydraulic system.
  • Be aware of how contaminants can affect a hydraulic system.
  • Be familiar with the purpose of reservoirs in a hydraulic system.

Basic Mechanics

  • Have an adequate understanding of the laws of mechanics (e.g., friction, equilibrium, inertia)
  • Comprehend the principles of applied forces.
  • Be familiar with the principles of absolute and atmospheric pressure.
  • Possess an understanding of the different types of gears, chain drives, belts, and bearings and their applications.

Reference Materials

Books

  • Electricity and Electronics by Howard H. Gerrish, and William E. Dugger, Jr., published by Goodheart-Willcox Company Inc. – ISBN 1-59070-207-7
  • Industrial Maintenance by Michael E. Brumbach and Jeffrey A. Clade, published by Thomson-Delmar Learning – ISBN 0-7668-2695-3
  • Electrical Motor Controls by Gary Rockis and Glen Mazur, published by American Technical Publishers Inc. - ISBN 0-8269-1207-9
  • Solid State Fundamentals by Gary Rockis, published by American Technical Publishers Inc. – ISBN 0-8269-1634-1

Websites


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