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Elevator/Escalator Apprenticeship Program
Entrance Examination 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, nor should individuals who have not completed some form of formal technical training either through a trade school, college, or military training use it as a sole preparation guide for examination purposes.  This study guide presumes the applicant has foreknowledge of the fields of electricity and mechanical/hydraulic principles.   This guide is divided into three portions, electrical/electronics studies and mechanical/hydraulic studies and sources of reference material (page 4).

    The electrical portion of the examination may include questions from any or all of the following areas of study:

      Ohm’s Law 

      • Demonstrate the ability to perform calculations to determine the unknown electrical quantity when given the 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 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.

The mechanical/hydraulic portion of the examination may include questions from any or all of the following areas of study:

Basic Hydraulics (Fluid Power)

  • 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 contaminates can affect a hydraulic system.
  • Be familiar with the purpose of reservoirs in a hydraulic system.

Basic Mechanics

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