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.
Voltage measured between phases.
Intentionally connected to earth through ground connection.
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?
1. To change the voltage of circuits from one level to another.
2. To connect or disconnect lines or equipment from each other.
3. To control the flow of power by adjusting the voltage and current.
A unit of measure for the amount of power that can be delivered to a load.
Kilovolt-Ampere or kVA
The network of interconnected transmission lines.
Unit of measure for the flow of electrons or current. Represented by the letter "I" on Ohm's wheel.
Electrically connected to a source of potential difference, or electrically charged to have a potential significantly different from that of Earth.
Alive, Live, or Energized
Compilation of conductors and electrical components that allow current to pass from a source to a load.
Allows current to flow with essentially no resistance.
Covers safety glasses.
Providing people with what they need in a gracious and helping manner.
Opposition to current flow in an electrical circuit. Measured in ohms ( Ω ) and represented with an "R" on Ohm's wheel.
A device that increases or decreases voltage.
Voltage measured between a phase and neutral.
The location in an electrical system where there is a change in ownership.
A circuit were voltage is constant.
Direct Current or DC
Unit of measure for frequency. In AC, the number of complete rotations of the generator in a second. The frequency of AC power in the US and Canada is 60 ____.
National Electric Safety Code, developed to enhance public and worker safety. It applies to lines and power stations in the US.
Unit of measure for electrical pressure. Commonly referred to as potential. Represented as "E" on Ohm's wheel.
Customer Average Interruption Duration Index
The conversion of electrical energy into another form of useful energy.
Unit of measure for electrical power.
System Average Interruption Frequency Index
Covers hard hats.
Where a source of energy is converted into electrical energy.
Name the common service voltages.
120/240 120/208 240/480 480 277/480 volts
A conductor that supplies power to a load.
A term that refers to the voltage when measuring the difference between two points.
Unit of measure of resistance in an electrical circuit.
The ability of one coil or conductor to induce voltage into another coil or conductor. Each coil shares the same core.
A conductor that provides a ground reference for the load.
What Council are we in and name a connecting Council.
Idaho is in the WSCC, and connects to MAPP, SPP, and ERCOL.
A pole structure that has a longer life span and is considered more aesthetically pleasing.
Tubular Steel Pole Structure
What considerations are taken into account when selecting a conductor type and size?
1. How much power the line needs to carry
2. Length of the line
3. Span lengths
4. Weather (environment)
5. Line losses
6. Cost of the conductor
Cuts in or out a portion of the transformer winding which adjusts the voltage to the conditions.
Load Tap Changer or LTC
Used to connect and disconnect lines and equipment by interrupting large amounts of current.
One or two smaller conductors that run parallel to the phases and are fastened to the top of the poles. These conductors are grounded.
Shield Wires or Static Wires
A waste of power in which the air around the conductor is ionized, accompanied by an audible and sometimes visible glowing effect.
A transmission structure with an operating voltage of 345 kV or below. Construction is relatively simple but structures require testing and treating of pole butts.
Wood Pole Structures
More than one conductor per phase.
What is the formula for sling tension?
Sling length over sling height times weight over number of slings.
How do you calculate hook strain?
Haul line (weight you are pulling) + weight of load
What is the formula for calculating haul line tension?
1.1 to the P power times W, over P. Where P equals parts and W equals weight.
Why are bundled conductors used?
1. To increase capacity
2. Reduce radio noise
3. Reduce Corona loss
What is the main objective for all transmission lines?
To deliver power with a minimum of loss.
The power to take property for the good of the general public following the payment or just compensation to the owner of the property.
The right to access property for the construction or maintenance of lines, structures, or components. May take form of easements or ownership of the land.
The popular choice for structures carrying 345 kV or greater. Built from pieces of angled steel bolted together.
Lattice Type Steel Structure
A circuit that provides more than one path for current to flow.
A deep-seated personal belief that is never compromised.
Point at which power is produced.
Name the common sub-transmission voltages.
44 kV 69 kV 115 kV 138 kV
A circuit that only provides one path for current to flow. The current remains constant but the voltage drops through resistance.
Excessive current flow in a circuit where the load is bypassed. A short circuited condition.
The point at which the power is used. The area of demand or customers.
Power produced by rotating a magnetic field near a conductor. The electrons in the conductor pulsate back and forth at a certain rate measured in hertz. Voltage is not constant.
Alternating current or AC
The simultaneous generation of electricity and useful thermal energy.
What is the formula for determining the weight of a cylindrical material?
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.
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.
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.
In parted blocks, friction overcomes the mechanical advantage after ____ parts, causing haul line tension to begin to rise.
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.
Name the parts of parted blocks.
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?
What is the typical line loss in an AC transmission system?
A tag that contains important information about electrical equipment such as a transformers weight.
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?
What is one individual conductor called in bundled conductor?
Do bundled conductors allow more amperage or voltage?
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.
What considerations are taken into account when determining the size of the right-of-way?
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?
What factors are taken into account when choosing a transmission structure?
Voltage of the line
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 ______.
Higher voltages require a larger right-of-way, larger structures, more insulation, and generally, more overall _____ per mile.
The inner portion of the shield wire contains a fiber optic cable. The fiber optic conductor will provide capacity for _____ and ______ communications.
The term substation is used synonymously with ______ station and _______ station.
Transmission substations that only have equipment that can connect or disconnect lines or equipment are commonly referred to as _________.
The substation where voltage is generally stepped up.
Transmission substations are typically installed to change the voltage levels to help ________ a system.
These substations are generally located in the load center.
These substations are typically located near a large load center.
Used to isolate lines and equipment in the substation.
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.
What are the four things you would find in the control house according to the book?
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.
What are the five environmental considerations that are a major factor in the siting, constructions, and operation of a substation?