Deck 7: Start-Stop Pushbutton Control

Question 1

What is a motor starter?

Answer 1

A motor starter is a contactor and overload relay combined.

Question 2

In schematics, what do dashed lines between components indicate?

Answer 2

In schematics, dashed lines between components indicate that the components are mechanically connected together.

Question 3

List the rules for numbering a schematic diagram.

Answer 3

The rules for numbering a schematic diagram are as follows:
1. A set of numbers can be used only once.
2. Each time you go through a component the number set must change.
3. All components that are connected together have the same number.

Question 4

Figure 7-2


In the accompanying figure, when the START button is pressed, current flows through ____________________ coil.

Question 5

What is the function of a holding contact?

Question 6

In schematics, electrical components are always shown in their energized or on state.

Question 7

A contactor is a relay that contains ____________________ contacts.

Question 8

In a schematic, any contact that is marked with the same letter or number as a coil is controlled by that coil regardless of where it is located in the schematic.

Question 9

A contactor may or may not contain auxiliary contacts.

Question 10

The START-STOP push button circuit is the basis for many other control circuits.

Question 11

What do wiring diagrams show?

Question 12

To simplify the task of converting the schematic diagram into a wiring diagram, ____________________ are added to the schematic diagram.

Question 13

____________________ diagrams show electrical components in their electrical sequence without regard for physical location.

Question 14

Figure 7-1


The accompanying figure shows a(n) ____________________ diagram of a basic START-STOP push button control circuit.

Question 15

Schematic or ladder diagrams are read from right to left and from bottom to top.