BOC 213

Credits: .7
Lecture: 6 hrs
Class Activities: 1 hr
Total: 7 hrs

Prerequisites: To be determined

Learning Outcomes/Competencies:
This class will prove useful to attendees in planning, retrofitting and/or troubleshooting basic electrical control systems. Attendees will be able to:

  • identify and modify electric control diagrams.
  • recognize diagram symbols and equivalent components.
  • comprehend basic electric control system strategies.

Texts:  STUDENT HANDBOOK: BOC 213 – Mastering the Fundamentals of Electric Control Circuits, plus course handouts

Teaching Props :

  • Circuit breaker, fuseable disconnect, relays (enough for class exercise), phase monitor, motor starter, time delay relay, start/stop push buttons (enough for class exercise), elapsed time meter, proximity switch, current transformer
  • Panel back pan with din rail, push button brackets, pre-cut wire (red, white and green), 120 VAC cord connector

Classroom Exercises and/or Hands-on Activities:

  • Draw a simple ladder diagram that contains a 3 wire latch circuit
  • Divide into groups, wire and test a three wire start-stop with latch relay


a. Test 100%

BOC 213 – Mastering the Fundamentals of Electric Control Circuits: Course Outline

1. Instructor and class introductions (15–20 minutes)

a. Attendee names and job description

i. Student expectations of class
ii. Questions students want or need addressed today

b. Overview of what will be covered in this class

2. Wiring Diagrams (5 min.)

3. Ladder Logic Diagrams (40-50 min)

a. Ladder diagram and components

i. Systems overview and power flow
ii. Circuit completion

b. International standard symbols comparing to equipment components

i. Line power (motors, motor starters, fuseable disconnects and circuit breakers)
ii. Control (buttons, selector switches, relays, time delays, elapsed time meters, current transformers, phase and voltage monitors)
iii. Three wire start stop (parallel and series w/ holding coil)

c. Flow chart of process and ladder diagram (cooling tower example)

4. Class draws simple ladder diagram one of the following (15-30 min)

a. Three wire Start/Stop w/ relay
b. HOA selector w/ start and holding relay
c. On/off selector, time delay w/relay

5. Separate into workgroups (60-75 min)

a. Wire simple three wire start/stop ladder control
b. Power up from 120v outlet and operate controller

6. Discussion, what have we learned today and test review (10-20 min)

7. Test (30 min)