Worksheetswle final
Total questions: 30
Worksheet time: 15mins
When are lines considered de energized
When they are disconnected
When they are tested
When they are disconnected, tested, and observed
When they are disconnected, tested, and properly grounded
How much amperage does it take to burn the skin and organs
1 amp
1-5 milliamps
16-100 milliamps
100-700 milliamps
A piece of equipment that has been disconnected from all normal sources of energy
Switch
Clearance
Open point
Breaker
What is the first objective of clearing lines
Ensure the safety of all employees and the public
Minimize negative impact on the electrical system
Minimize the number of customers who will be out of service
Protect switches
What is the first step of a clearance procedure
Establish and issue clearance
Request clearance in writing
Create clearance plan and confirm detail
Return system to neutral
What is the last step of a clearance procedure
Establish and issue clearance
Request clearance in writing
Create clearance plan and confirm detai
Return system to neutral
OSHA requires all devices that are used as a clearance point to be ______ when in use
Open
Closed
Locked out
Tagged out
What occurs when a nearby energy source such as a transmission line electrifies a disconnected lines
Convection
Induced voltage
Radiated voltage
Forced voltage
Equipment designed to store voltage may retain a charge long after being disconnected
Induced voltage
Convection
Capacitance
Static charge
OSHA requires waiting how long before installing grounds on a disconnected capacitor
10 minutes
15 minutes
5 minutes
You don’t need to wait
Introduces enormously high levels of voltage into a work site
Static charge
Lighting up to 100million volts
Lighting up to 500 million volts
Capacitance
Warm winds blowing across the surface of conductors can create what?
Capacitance
Lighting
Static charge
Convection
When current travels backwards through a conductor
Static charge
Back feed
Capacitance
Induction
What is the first step in the grounding process
Disconnect
Test
Identify
Ground
The line is not officially de-energized until
Your Forman says it is
Your safety director says it is
It is disconnected
You test and ground it
Screw type ground rod placed deep into the earth to provide an effective path for current to fl
Guy wire
Ground grid
Temporary ground rod
System neutral
This conductor is installed on transmission lines above the phase conductors for the purpose of intercepting lighting
System neutral
Lighting wire
Static/shield wires
Ground/shield wires
Protective grounds act as a direct low-resistance path to ground in order to?
Minimize the time it takes to trip the circuit
Protect the conductor
Define the resistan
Quantify the path to ground
Protective grounds act as a direct low-resistance path to ground in order to?
Protect the fault current
Protect the conductor
Define the resistan
Limit the current flow and voltage drop across the line workers bo
—————- provides, at the structure that is being worked on, a low resistance short circuited connection to ground source
Bracket ground
Equipotential zone
System neutral
B phase
Used primarily to trip the line’s protection devices as quickly as possible
Bracket grounding
Equipotential zone
System neutral
B phase
————must be installed to protect each employee
Equipotential zone
Cluster bracket
Bracket grounding
Protective grounds
Connect to ground source first, then to conductor or equipment. Remove from conductor first, then remove from neutral
Golden rule of grounding
Law of grounding
Phase to phase fir
Bracket grounds
Ground cables should be
Free of broken strands
Eye screw of the ground clamp should be bent
Should have cracks and warping
Should have some free play
What/who can determine the resistance of the clamps and cable
Visual inspection is adequate
Only testing
Your safety supervisor
Your foreman
Any equipment that was subject to fault current…..
Must be removed from use immediately for testing
Must be thrown out
Inspected and returned to service
Will burn up
Grounding plan: creation of EPZ, grounding cable size, grounding cable placement, and__________
Test
Identify
Fault current
Clean
Uninterrupted flow of current
Resistance
Back feed
Continuity
Convection
Conductive mats that help provide an EPZ between the work surface and the equipment
Grounding spike clamp
Dead end cap
Feed through bushing
EPZ Mat
The first step in the grounding process on an underground system
Test voltage
Review circuit maps and work order prints
Install protective grounds
Disconnect the cables to be cleared
