319 - Introduction to Ladder Logic, Pushbuttons

True

A dot on a ladder diagram indicates a terminal or wire connection.

II

A horn is shown at ___ in Figure 320.11 as a NEMA or industry standard symbol.

True

A line on a ladder diagram represents a wire.

wiring (or connection)

A(n) ___ diagram for a 3Ø motor and its starter illustrates both the control and power circuits.

closed

Contacts that are spring-held in a closed position, or state, are referred to as normally ___.

open

Contacts that are spring-held in an open position, or state, are referred to as normally ___.

maintained

Contacts that retain their state after a force is removed are called ___.

momentary

Contacts that return to their original state after a force is removed are called ___.

ladder (or line)

Control circuits are generally illustrated using ___ diagrams.

L2

For a 2-wire control circuit, the grounded conductor (neutral) is permitted to be connected to ___.

b

In a control circuit which of these drawings shows the components connected to operate correctly?

none of these show the maximum

In a control circuit which of these drawings shows the maximum number of control relay coils that can be connected line-to-line in parallel?

True

In a control circuit, all wires connected to L2 will have the same wire reference number.

normally closed

In a numerical cross-reference system, ___ contacts are underlined.

bell

NEMA or industry standard Symbol I, shown in Figure 320.11, represents a ___ when used in a ladder diagram.

True

On a ladder diagram, the branch circuit conductors are represented by Line 1 (L1) and Line 2 (L2).

any one of the switches is

Refer to Diagram I in Figure 320.15. The load is energized when ___ closed.

series

Refer to Diagram II in Figure 320.15. The load is connected in ___ with the switches.

all the switches are

Refer to Diagram II in Figure 320.15. The load is energized when ___ closed.

maintained

Refer to Figure 320.201. Symbol II is a switch that has ___ contacts.

series

Refer to Figure 324.51. Component is connected in ___with component .

c

Select (as required) the NEMA or industry standard symbol for the component shown below. This momentary switch is spring held in the position shown and is used to release a door magnet.

a

Select (as required) the NEMA or industry standard symbol for the component shown below:

b

Select (as required) the NEMA or industry standard symbol for the component shown below:

d

Select (as required) the NEMA or industry standard symbol for the component shown below:

NEMA

Standardized ___ symbols are utilized in wiring diagrams.

siren

Symbol II, shown in Figure 320.11, represents a ___ when used in a ladder diagram.

II

Symbol ___ in Figure 320.14 represents the NEMA or industry standard symbol for a fuse.

I

Symbol ___ in Figure 320.14 represents the NEMA or industry standard symbol for a light.

I

The NEMA or industry standard symbol for a SPDT, single-break switch is shown at ___ in Figure 320.12.

II

The NEMA or industry standard symbol for a SPST NC, single-break switch is shown at ___ in Figure 320.12.

V

The NEMA or industry standard symbol for a SPST NO, single-break switch is shown at ___ in Figure 320.12.

buzzer

The NEMA or industry standard symbol for a ___ is shown at III in Figure 320.11.

III

The NEMA or industry standard symbol for a buzzer is shown at ___ in Figure 320.11.

IV

The NEMA or industry standard symbol for a double-break, momentary-contact, single-circuit, normally open pushbutton switch is shown at ___ in Figure 320.12.

III

The NEMA or industry standard symbol for a fuse is shown at ___ in Figure 320.13.

I

The NEMA or industry standard symbol for a light is shown at ___ in Figure 320.13.

II

The NEMA or industry standard symbol for a line-to-line connected load, such as a fan motor or a garbage disposer, is shown at ___ in Figure 320.13.

III

The NEMA or industry standard symbol for a momentary-contact, single-circuit, normally closed, double-break pushbutton switch is shown at ___ in Figure 320.12.

A

The abbreviation used to indicate an amber indicator light is ___.

I, II & III

The basic components of a control circuit include ___. I. power source II. switch contacts III. loads

True

When using a ladder diagram to wire a control circuit, all wires with the same wire number will have a common connection.

both I & II

When wiring a control circuit, good wiring practice is to ___.I. install wire markers II. mark completed connections on diagram

as many as required

Where connected across-the-line (line-to-line) in a control circuit, ___ is the maximum number of pilot device contact sets that can be series-connected.

Ladder

___ diagrams are generally used to illustrate control circuits.

Select the NEMA or industry standard symbol for a set of transformer windings (showing both primary and secondary windings).

a

Select (as required) the NEMA or industry standard symbol for the component shown below:

b