Electrical Control Drawings

Question 1

What are the four basic types of control drawings?

Answer 1

Wiring diagrams
Schematic (Ladder, Elementary) diagrams
Block diagrams
Interconnection (termination schedule, pinout) diagrams

Question 2

In a pinout diagram, what is meant by the “top view”?

Answer 2

Looking down the cable at where the wires would terminate.

Question 3

Is a block diagram a very detailed representation of an electrical system?

Answer 3

No.

It simply shows interconnection of equipment and processes by a single line and “blocks”

Question 4

If troubleshooting a system or process, would you use a wiring diagram?

Answer 4

Generally no.

You would want to use a schematic diagram as it simply illustrates the electrical sequence.

Question 5

What is the symbol for an overload heater?

Answer 5

It is like two sickles touching with handles pointed 180* away from each-other, where one’s lateral rotation is reversed.

Question 6

What is the symbol for a normally open push button?

Answer 6

A bar contact floating above two terminals separated by an air gap.

Question 7

Where are the load devices normally located on a schematic diagram?

Answer 7

Aligned vertically with each-other and on the right hand side.

Question 8

What is the symbol in a schematic diagram for a normally closed contact actuated by a relay coil?

Answer 8

Two vertical lines with a slash through them and labeling to identify which coil actuates the contact

Question 9

What is represented by a dashed line between symbols in a schematic diagram?

Answer 9

Mechanical interlocking of the device(s).

Question 10

When drawing a schematic diagram, what is the state of the system?

Answer 10

It is drawn in a “powerless” state.