When would DC transmission be used?
To move large blocks of power over long distances.
Name the common transmission voltages.
765 kV 500 kV 345 kV 230 kV
Your internal believe regarding safety issues.
Safety Attitude
SAIDI
System Average Interruption Duration Index
NERC
North American Electric Reliability Corporation, overseas 10 reliability councils, nine in the US and one in Canada.
Name the common distribution voltages.
2.4 kV / 4.16 kV 7.2 kV / 12.470 kV 7.62 kV / 13.2 kV 12 kV / 20.8 kV 14.4 kV / 24.5 kV 19.9 kV / 34.5 kV
What is the common transmission voltage range?
230 kV to 765 kV
What is the common sub-transmission voltage range?
44 kV to 138 kV
What is the common distribution voltage range?
2 kV to 34.5 kV
Used to isolate electrical energy from ground.
Insulator
Voltage measured between phases.
System Voltage
Intentionally connected to earth through ground connection.
Grounded
Optimum voltage range for generation.
13.8 kV to 24 kV
Who is the customer?
Utilities and the utility rate payers.
What are the three primary functions of substations?
What is the formula for determining the weight of a square or rectangular material?
Weight = Length X Width X Height X Weight of Material
When a rope is pulled tight very quickly and with great force, resulting in a substantial increase in weight or tension.
Shock Loading
What is the formula for RWLL?
The maximum load that can be applied to a rope while ensuring longevity and taking the efficiency of any knots tied in the rope into account.
Reduced Working Load Limit or RWLL
The maximum load applied to a rope to ensure longevity of the rope.
Working Load Limit or WLL
An arbitrary number determined by your company which is used to determine the working load limit, five is common in this industry. It commonly ranges from 5-9.
Design Factor
The average force in pounds needed to break a rope, as determined by the manufacturer.
Catalog Breaking Strength or CBS
List the common sling configurations from strongest to weakest.
Basket
Vertical
Choker
In parted blocks, friction overcomes the mechanical advantage after ____ parts, causing haul line tension to begin to rise.
10 parts
When referring to parted blocks, the _____ end should have the haul line coming out of it and the _____ end should be attached to the load.
Standing
Running
Name the parts of parted blocks.
Hook
Safety Latch
Swivel
Shell
Sheaves
Center Pin
Becket
Parts
Haul Line
Where is the weight rating located on parted blocks?
The hook and the shell.
What is the typical line loss in a DC transmission system?
4%
What is the typical line loss in an AC transmission system?
9%
A tag that contains important information about electrical equipment such as a transformers weight.
Nameplate
What is the main function of a transmission system?
To deliver large blocks of power from a source to the load.
What is the main determination for the size of an insulator?
The voltage
What is one individual conductor called in bundled conductor?
Sub-conductor
Do bundled conductors allow more amperage or voltage?
Amperage
The main objective of delivering power with a minimum of loss has a major bearing on the selection of a voltage level when engineering a transmission line. What other considerations are taken into account?
Length of the line
Amount of power to be delivered
Voltage of existing system
Cost of losses
What is the main function of a shield wire?
To provide lightning a path to ground.
The type of transmission that is used in large cities where right-of-way is very expensive.
Underground Transmission
What considerations are taken into account when determining the size of the right-of-way?
Voltage
The type of structure
Horizontal movement of the phase conductors
The level of the magnetic field
What must the right-of-way be cleared of?
Trees
Vegetation
What factors are taken into account when choosing a transmission structure?
Voltage of the line
Right-of-way size
geographical terrain
weather
size of conductor
whether two circuits are needed right away or in the future
Name the four types of insulators commonly used on transmission lines.
Porcelain suspension insulators
Porcelain line post insulators
Polymer suspension insulators
Polymer line post insulators
A suspension insulator hanging in a deadend configurations would require a higher ______.
Mechanical rating
Higher voltages require a larger right-of-way, larger structures, more insulation, and generally, more overall _____ per mile.
Expense
The inner portion of the shield wire contains a fiber optic cable. The fiber optic conductor will provide capacity for _____ and ______ communications.
Voice
Data
The term substation is used synonymously with ______ station and _______ station.
Power
Supply
Transmission substations that only have equipment that can connect or disconnect lines or equipment are commonly referred to as _________.
Switching Stations
The substation where voltage is generally stepped up.
Generation Substation
Transmission substations are typically installed to change the voltage levels to help ________ a system.
Integrate
These substations are generally located in the load center.
Distribution substations
These substations are typically located near a large load center.
Sub-transmission substations
Used to isolate lines and equipment in the substation.
Disconnect switches.
Provide a reduction in the voltage and current so the power flow can be measured.
Current and Potential Transformers
The devices in the substation that sense abnormal flows of voltage and current, which is used to disconnect lines and equipment during trouble conditions.
Current and Potential Transformers
These devices are connected and disconnected from the system based on the dynamics of the flow of power.
Capacitors and Reactors
These devices automatically adjust the voltage as required in the absence of an LTC.
Voltage regulators
What are the four things you would find in the control house according to the book?
Relays
Meters
Computers
Backup DC batteries
What does the ground grid provide a ground reference source for?
Transformers, neutral conductor, and other station equipment.
The ground grid ensures the safety of the workers inside the station and the public who may be near the fence by limiting the ground _______ differences.
potential
What are the five environmental considerations that are a major factor in the siting, constructions, and operation of a substation?
Appearance of the substation
Electromagnetic fields
Sound
Oil Spill Containment
Fencing