13-EHS- Section 4 Flashcards
According to the Electrical Safety Hand Book, What are the three parts of a typical electrical system?
a. Generation, Transmission, Distribution
b. Voltage, Current, Resistance
c. Wood Structures, Steel Structures, Concrete Structures
d. Poles, Insulators, Conductors
A
There are three parts to a typical electrical system; Generation, Transmission and Distribution. Electricity is transported throughout the province of Ontario by transmission systems. Transmission lines bring power into cities on wood structures, or steel towers at voltages from 69,000 to 500,000
volts. The design can vary from a single wood pole for 69,000 to 115,000 volts to steel structures for 115,000 to 500,000 volts
According to the Electrical Safety Hand Book, What is the primary purpose of transmission lines?
a. Distribute electricity to homes
b. Transmit electricity over long distances
c. Generate electricity from renewable sources
d. Regulate voltage in the power grid
B
Transmission
lines bring power into cities on wood structures, or steel towers at voltages from 69,000 to 500,000 volts
According to the Electrical Safety Hand Book, At what voltages do transmission lines typically operate in Ontario?
a. 1,000 V - 10,000 V
b. 69,000 V - 500,000 V
c. 115 V - 230 V
d. 1,000,000 V - 5,000,000 V
B
at voltages from 69,000 to 500,000
volts. The design can vary from a single wood pole for 69,000 to 115,000 volts to steel structures for
115,000 to 500,000 volts
According to the Electrical Safety Hand Book, How is the voltage of a transmission line determined when working in close proximity?
a. Measure it with a handheld device
b. Contact Hydro One and provide alphanumeric number on the steel structure or pole
c. Count the number of insulators
d. Check the color of the power lines
B
Determine the
voltage by contacting Hydro One and providing
the alpha numeric (number) found on the leg of the steel structure or the pole.
According to the Electrical Safety Hand Book, What is the recommended distance to keep from live high voltage transmission lines?
a. 6 meters
b. 10 meters
c. 20 meters
d. 50 meters
A
An easy to remember rule for working around
live high voltage transmission lines is to keep at least 6 meters (20 t) away. If you need to work closer, first determine the voltage.
According to the Electrical Safety Hand Book, What is the purpose of bell-type insulators on power lines?
a. To support the structure
b. To carry the conductor on top
c. To enhance aesthetics
d. To prevent corrosion
B
Bell-type insulators are suspended from the structure with the conductor running on the bottom of the stack of insulators.
According to the Electrical Safety Hand Book, In the distribution system, what voltages are common for local distribution transformers?
a. 69,000 V - 500,000 V
b. 2,400 V - 44,000 V
c. 120/240 V - 347/600 V
d. 500,000 V - 1,000,000 V
B
From a substation the voltages are reduced to 2,400 to 44,000 volts for distribution to local
distribution transformers
According to the Electrical Safety Hand Book, Where is the Hydro One pole number typically located?
a. On the ground
b. On the transformer
c. On a silver plate about 1.5 meters from the ground
d. On the insulators
C
For example, Hydro One Networks’ pole
number is a six character alpha numeric code
located on a silver plate about 1.5 metres (5 t)
from the ground. This number identifies location as well as valuable information about equipment on the pole.
According to the Electrical Safety Hand Book, What is the purpose of fuse cutouts in distribution systems?
a. To measure voltage
b. To prevent damage to transformers and customer equipment
c. To store energy
d. To regulate current flow
B
The fuse cutout acts like a circuit breaker in a house. If there is a power surge or short in the
line, the fuse cutout will blow open preventing
damage to the transformer and customers’ equipment. Other equipment that is found in distribution systems includes switches, regulators and capacitors.
According to the Electrical Safety Hand Book, What is the function of reclosers in power line protection?
a. Open circuits permanently
b. Automatically close and re-energize the power line after a fault
c. Measure voltage fluctuations
d. Control distribution transformers
B
Both transmission and distribution power lines are protected by automatics circuit breakers and by “Reclosers” shown here. When a power line is tripped out (i.e. open)
due to a fault, the automatic breaker or recloser will, after a short period of time (typically a fracion of a second to minutes), attempt to close and re-energize the power line
What type of insulator is used for 44,000 volts or less on distribution power lines?
a) Pin-type insulator
b) Bell-type insulator
c) Composite insulator
d) Steel insulator
A
The power lines
are attached by insulators to prevent the low of electricity to the ground. Pin type insulators carrythe conductor on top and are used for 44,000 volts or less.
According to the Electrical Safety Hand Book, What information does the Hydro One Networks’ pole number provide?
a) Voltage of the power line
b) Location and equipment details
c) The number of insulator bells
d) Type of wood used in the pole
B
This number identifies location as well as valuable information about equipment on
the pole. Emergency responders are not to place themselves in a dangerous situation to get the number
According to the Electrical Safety Hand Book, What precaution should be taken when using water on electrical fires involving wood pole structures?
a) Apply water directly to the pole
b) Wear minimal protective gear
c) Keep at least 10 meters away from the base of the poles
d) Use foam as a fire suppressant
C
Keep Back Minimum 10 m (33 t)
According to the Electrical Safety Hand Book, What is the minimum safe distance for applying water to live electrical equipment with a voltage of 15,000 volts?
a) 1.5 meters
b) 4 meters
c) 7 meters
d) 10 meters
B
751 to 15,000 4 metres (13 t)
According to the Electrical Safety Hand Book, When encountering fallen wires, what distance should emergency responders keep bystanders back from the wires?
a) 2 meters
b) 5 meters
c) 10 meters
d) 15 meters
C
Stand well back, at least 10 metres (33 t) or more away. Look for and locate all wire ends. They may be on the ground or suspended in the air. If a live wire touches a car, truck, metal fence or any other conducive object that object will also be capable of killing people. A pool of water will also become deadly if a live wire has fallen into it. Keep bystanders back at least 10 metres (33 t).Establish the safe zone, at least 10 metres (33 t) away from wires and anything the wires may be touching. If a wire has fallen onto a fence or metal object, electricity may be conducted to other points some distance away. You will need to ensure all potentially electrified objects are inaccessible. Inform other emergency responders of the hazards.
