Chapter 1 Flashcards
Series and Parallel Circuits
What’re the 3 key elements in order for Basic Electrical Circuits to function properly?
- ) Source of electrical pressure (Voltage)
- ) Conductor
- ) Load
How is Voltage a key element?
It is the force that will push the electrons through the conductor.
How is a Conductor a key element?
Conductors are necessary to transmit energy to the point where it will be used.
How is Load a key element?
Load is a device that uses the electrical energy from a source to accomplish some useful purpose.
What is an Open Circuit?
An incomplete path where electrons are unable to flow through a conductor and provide power.
What will the load limit?
The amount of current that can flow through a conductor by providing resistance.
What is a Short Circuit?
A circuit that does not have a load, or in which the load has been bypassed.
How can circuits be protected from short circuits?
With fuses.
What is a fuse?
An intentionally weakened point in a circuit that burns open when current flow is excessive.
What does a Short Circuit have?
Very low resistance.
What happens as electrons flow through a conductor?
They collide with another and create heat. When current flows, billions of there collisions take place every second.
What happens if too much current flows?
The capacity of the conductor will be exceeded and the conductor will melt.
How is a fuse designed?
As an intentionally weakened point in a circuit to melt at lower amperage than the conductor, thereby protecting it.
What are the two basic types of circuits?
- Series
- Parallel
- Combo
The series circuit is probably the _____ type of circuit.
Simplest
How does current flow in a Series Circuit?
Only one path for current to flow.
Because there is only one path for current flow, how is the current at any point in the circuit?
The same at any point
How are Series Circuits most commonly seen?
In lighting applications.
In the power delivery industry what are Series Circuits considered?
Impractical
In comparison what do Parallel Circuits have compared to Series Circuits?
Practical Value.
What do Parallel Circuits have?
Multiple for current to flow.
What are Combination Circuits?
Consist of both series and parallel parts.
What Circuit type are power lines?
Combination Circuit
What is said to be in series?
Anything that is connected directly across two points of different potential.
What principal is important for a lineworker to understand?
Anything that is connected in series will have current flow through it unless resistance is sufficient to prevent it.
What happens if a lineworker is between two points of different potential?
Current will flow through the body causing injury or death.
Even when wearing Protective equipment to do hot work, the worker should never place himself in _____?
Series
If viewed individually, how is nearly all line equipment connected?
In Series
What kind of devices may be connected in series?
- Regulators
- Reclosers
- Sectionalizers
- Switches
What does it mean when these devices are connected in series with the line?
That all of the line current will pass through them.
What does any device connected down line from these devices cause?
Increase in current flow through them.
If a certain amount of current is required for the circuit to operate properly what must voltage be?
High enough to maintain the proper current flow.
How does Voltage work in a Series Circuit?
It requires a certain amount of voltage to push a given current through a given amount of resistance.
What is this value known as?
Voltage Drop
What happens to to voltage as it is ran through a resistance?
It drops and less voltage will be available to push current through the next load.
By the time current flows through the last load connected to the circuit, what happens to voltage?
It is all used up.
What must the voltage applied to a circuit equal?
The sum of all the voltage drops across all the resistors.
Why are power lines considered Combination Type Circuits?
Because the equipment that is connected in series with the line; However the layout of the circuit is predominantly parallel.
How many paths do Parallel Circuits have?
More than one.
How are sections divided in the overall power system?
At the point where voltage is transformed.
How are parallel circuits distinguished?
By the fact that the electrical values seen by the source are dependent upon the individual loads.
By adding more load what happens to current flow?
It will increase and the source will supply more power.
We can continue to add load to the transmission line until?
The capacity of the wire is reached, or until the source reaches its maximum output.
What principle holds true for the electrical system?
At each point voltage changes, a new parallel circuit can be viewed.
What can we find if you follow the electrical system to the point of utilization?
The entire layout is a parallel.
What is an advantage to having a parallel type circuit?
This design has the distinct advantage of providing reliability.
Each load connected in a parallel circuit will have a voltage drop equal to?
The applied voltage.
Each device connected to a parallel circuit draws what?
A certain amount of current.
What happens to current flow as deices are added on a line?
It will increase.
What is the total current supplied by the source?
The addition of the current demands of the individuals.
What does a load produce?
Resistance
What does a source produce?
Electrical pressure or voltage
Three parts of a fuse
- Stranded Cable
- Steel Support Wire
- Fusible Element
How does current behave in a parallel circuit?
Voltage can be different at any given point in the circuit
Formula for Current
E=I x R
What happens when devices are added to the line in a parallel circuit
Current flow through the conductors will increase
Total current supplied by the source in a parallel circuit
The addition of the current demanded of the individual loads
