Ch. 6 Mechanical Input Control Devices

Pushbuttons

_____are the most common control switches used on industrial equipment.

Legend plate

A(n) _____ is the part of switch that includes the written description of the switch's operation.

operator

A(n) _____ is the device pressed, pulled, or rotated by the individual operating the circuit.

Jumbo mushroom

A _____ button operator can be operated from any angle and is used in applications that are hiring fast operations such as emergency stops, motor stops, and valve shut offs.

Rotated

A selector switch is a switch with an operator that is _____ to activate the electrical contacts

Truth

A ______ table is made in position near the switch to illustrate each position and each contact

X

A ______ is placed in a truth table if a contact is closed in any position.

Joystick

A _____ is an operator that selects one to 8 different circuit conditions when it is shifted from its center position

Dot

Line diagrams may use a ____ to indicate which joystick position will operate the contacts

Hoist

The most common application of a joystick is in controlling a _____

Limit

A ____ switch is a mechanical input that requires physical contact of the object with the switch actuator

Contact pole

A ____ is not a basic actuator used on limit switches

Two

A fork lever actuator is an actuator operated by one of ____ roller arms

Push roller

A ____ actuator is an actuator operated by direct forward movement into the limit switch

Two hand safety circuit

A ______ is not a common foot switch application

2

Most foot switches have ____ positions

Off

In a foot switch, the _____ position is normally spring loaded so that the switch automatically returns to that position when released

27.68

1 psi = ______ in WC

Barrow Meter

A ___ is not a common sensing device used by most pressure switches

Piston

____ sensing devices are used for high pressure applications

Deadband

______ is the amount of pressure that must be removed before the switch contacts reset for another cycle after the set point has been reached and the switch has been actuated

Temperature

_____ switches are control devices that react to heat intensity

Air Compression

An ______ system is not a common application of temperature switches

Rises

In a cooling system, as the ambient temperature ______, the switch contacts close and turn on a cooling device

Flow

______ is the travel of fluid in response to a force caused by pressure or gravity

Flow

A ___ switch is a control switch that detects the movement of a fluid

Sprinkler refrigeration and water treatment

Applications that use flow switches to detect the presence or absence of flow include ______ systems

Level

A ____ switch is a switch that detects the height of a liquid or solid inside of a tank

Mechanical

_____ level switches use a float that moves up and down with the level of the liquid and activates electrical contacts at a set height

Conductor

A _____ probe level switch is a level switch that uses liquid to complete the electrical path between 2 conductive probes

Capacitive

A ____ level switch detects the dielectric variation when a product is in contact with the probe and when the product is not in contact with the probe

Resistive

_____ loads are the least destructive loads to switch

Operating

A pressure switch is rated according to its _____ pressure range

Flow

Most ______ switches use a paddle to detect the movement of a product