Switching Circuits Flashcards
The abbreviation for normally closed switches is what?
NC or N/C
The terms normally open or normally closed signify what?
The position taken by the device when no force is acting upon it.
What does it mean if a switch or contact is momentary?
It signifies that the device changes state only when acted upon by an outside force.
What does it mean if a switch or contact is maintained?
It signifies that the device changes state when acted upon by an outside force and remains in that state when the force is removed.
What is a switch pole?
The number of separate circuits that a switch controls.
A single-pole switch controls two circuits, true or false?
False, it only controls one circuit.
How many circuits does a double-pole switch control?
Two circuits.
The number of ‘throws’ in a switch contact determines what?
It determines how many different switching positions a switch can be in.
A simple light switch is an example of a single break type device or a double break contact device?
A single break type device.
What are single break and double break contacts?
Single break and double break contacts refer to the number of circuit breaking contacts a device has.
One way to classify switches is by the connections they make. What two factors determine what types of connections a switch makes?
The polls and the throws.
The two most common types of throws are:
Single-throw and double-throw.
What is a single-throw switch?
A single-throw switch is a simple on/off switch that connects or disconnects two terminals.
What is a double-throw switch?
A double throw switch connects an input terminal to one of two output terminals.
How many terminals does a double-throw switch have?
What are they called?
3.
- The common terminal
- A
- B
Winch controls and engine starters are examples of which type of switch?
A momentary switch.
A double-pole double-throw (DPDT) switch has how many terminals?
6.
- 2 for the inputs
- 2 for the A outputs
- 2 for the B outputs
The abbreviation for normally open switches is what?
NO or N/O
What is a schematic diagram or drawing?
A schematic diagram or drawing shows the logical sequence of operation of the circuit without regard to the physical location of the circuit components.
Schematic diagrams are also referred to as ___ diagrams or ___ diagrams?
Elementary diagrams or ladder diagrams.
The two vertical lines on a schematic diagram represent what?
The power source.
What are ‘rungs’ in a schematic diagram?
Horizontal conductors
What is a wiring diagram?
A wiring diagram is a graphic representation of a circuit showing the electrical interconnection of circuit components and their relative physical location.
In most circuits you work with, the white wire is the grounded conductor and is properly called the ___ ___.
Identified conductor
What is the common name given to the two wires that connect three-way or four-way switches together?
Travellers
Which conductor should be connected to the brass screw of lampholder in a switched circuit?
The switch leg (coloured)
Which conductor should be connected to the silver screw on a duplex receptacle?
The identified conductor (white)
A standard door chime unit consists of which three components?
- two solenoids (electromagnetic coils)
- two spring-suspended plungers that slide back and forth within the solenoids when the solenoid is energized and
- two chime plates
