SOLUTION RATED A+
✔✔the ground grid provides what - ✔✔path to ground for lighning
a ground for all substation equipment
ensure the safety of workers
ensure the safety of public near fence
ground source for all lines coming in and out of substation
✔✔what are the 3 environmental considerations - ✔✔apperance, sound, and oil spill
containments
✔✔what are designed to interrupt current under fault conditions by using protective
relays and removes sections from service - ✔✔circuit breakers
✔✔breakers that are filled with oil - ✔✔oil circuit breakers
✔✔breakers filled with compressed gas known as sf6 - ✔✔sulfur hexafluoride circuit
breakers
✔✔breakers filled with compressed air - ✔✔air circuit breakers
✔✔breakers that utilze a vacuum - ✔✔vacuum circuit breaker
✔✔what provides equipment protection for transformers, lines, cables, and capacitor
banks - ✔✔circuit switches
✔✔what reduces the current levels in the lines - ✔✔current transformers
✔✔what steps down the circuit's high voltage to a desired secondary voltage -
✔✔potential transformers
✔✔what are protective devices that prevent damage to equipment by limiting surge
voltages - ✔✔lightning arresters
✔✔what houses equipment such as switchboard panels, batteries, battery chargers,
supervisory control, powerline carriers, meters, and relays - ✔✔control house
✔✔contains meters, control switches, and recorders located in the control house -
✔✔control panels
✔✔what controls key equipment if power is lost at the substation - ✔✔dc batteries
,✔✔what begins as the primary circuits leaves the substation and ends as the secondary
service enters the customer's meter socket - ✔✔modern distribution systems
✔✔what is the most common type of primary phase - ✔✔wye
✔✔what contains 3 phases and a neutral - ✔✔wye
✔✔most common voltages in distribution are - ✔✔2400/4160, 7200/12470, 7620/13200
✔✔when reading voltages on overhead, the first number is - ✔✔phase to ground
✔✔when reading voltages on overhead, the second number is - ✔✔phase to phase
✔✔you can calulate phase to phase voltage by - ✔✔multplying phase to ground by
1.732
✔✔what primary configuration is less common and older - ✔✔delta
✔✔which system will require the transformer to have two phases to energize - ✔✔delta
✔✔on a distribution system, each wire carries one phase of a three phase feeder -
✔✔true
✔✔on distribution system layouts, which design is most reliable - ✔✔loop
✔✔on distribution system layouts, which design is least reliable - ✔✔radial
✔✔primary volage is also known as - ✔✔high side or source
✔✔secondary voltage is also known as - ✔✔low side or load
✔✔distribution line consists of three main elements - ✔✔primary, secondary, and
services
✔✔residentia customers are typically served with what voltage - ✔✔120/240 single
phase
✔✔these are also low voltage but will run from pole to customer on overhead systems
and from pedestal to customers on undergroud systems - ✔✔services
✔✔all poles come in increments of - ✔✔5'
✔✔the most popular choice for powerline construction is - ✔✔wooden pole
, ✔✔to calculate depth of wooden pole, the standard formula is - ✔✔pole length x 10% +
2'
✔✔often times om dead-end poles or angle poles, we will set them - ✔✔1' deeper than
standard
✔✔pole brands (birth marks) include what information - ✔✔manufacture
when pole was treated
size length and class
type of wood
✔✔a guy wire that attaches from top of pole to ground level - ✔✔down guy
✔✔a guy that is used for clearance over sidewalks - ✔✔mast arm or sidewalk guy
✔✔a guy wire that attached to the top of a pole with energized conductor to top of pole
with non energized conductors - ✔✔stub guy
✔✔a guy wire that attached to the top of a pole with energized conductor to top of
another pole with energized conductors - ✔✔span guy
✔✔a guy wire that attached to the top of pole to a point below the top of the adjacent
pole - ✔✔head guy
✔✔a pole that is used as a brace - ✔✔push guy
✔✔what are insulators made out of - ✔✔glass, porcelain, or polymer
✔✔the most common types of conductors are - ✔✔acsr and aaac
✔✔how long should you wait before tieing in the conductor after stringing it - ✔✔24 hrs
✔✔what three things affects the power that is distributed by a distribution system -
✔✔transformers, voltage regulators, and capacitors
✔✔when sagging wire, there are four major components to calculating the tensions
which are - ✔✔temperature
size of wire
type of wire
length of ruling span