4-Week We were registered for Transmission and operation of
Colombo region inthe rst week on our training. We encounter several
new areas about theprotections in the grid substations .We referred
one of the single line diagram ofthe substation. Then we identi ed
some basic connections in the switchyard.Supplied protection
guidelines conveyed us how important of the schemes of
protection in a substation. The features of !s system and the
"!S system wereseparately understood .The importance of !S is it
reduce the space occupied bylarge switchyard. The cost of !S is
very high but the reliability and e#ciency ishigh.
The maintainace of the transmission line is very important.When
the lines are not suit to the minimum rating then those were needed
toreplace. When the cables are getting old its length will
increase. !t will reduce thecross section and increase the
resistance. !t will also increase loss. $ue to thisfre%uently
monitoring and replacing of wires are important. "s a reliable
powersystem also needed to change insulator strings when them were
&ashed.
When there is a maintainance it is important to consider safety
of the workers.Thus it is needed to interrupted power. 'ut it is
not a good sign of reliabletransmission system. So needed to do
maintaince while current is running .Thusthis kind of sub(ect named
)ot line maintains. *nder this sub(ect mainly dotension insulators
replacement+ suspension insulators replacement+ insulatorwashing+
hardware ,ing .The crew of the )ot ine maintainace use
severale%uipment which highly insulated. We got some understand of
the hot linemaintains while crew of the )ot ine maintainace
changing insulator strings andwires in transformers of Sapugaskanda
ower plant.
